Building with -Wshadow reports several potential issues with mlx5 driver.

[1123/3418] Compiling C object
drivers/libtmp_rte_net_mlx5.a.p/net_mlx5_mlx5_rss.c.o
In file included from ../drivers/net/mlx5/mlx5_rss.c:19:
../drivers/net/mlx5/mlx5_rx.h: In function ‘mprq_buf_replace’:
../drivers/net/mlx5/mlx5_rx.h:448:39: warning: declaration of ‘rep’ shadows a
previous local [-Wshadow]
  448 |                 struct mlx5_mprq_buf *rep;
      |                                       ^~~
../drivers/net/mlx5/mlx5_rx.h:424:31: note: shadowed declaration is here
  424 |         struct mlx5_mprq_buf *rep = rxq->mprq_repl;
      |                               ^~~
[1124/3418] Compiling C object
drivers/libtmp_rte_net_mlx5.a.p/net_mlx5_mlx5_ethdev.c.o
In file included from ../drivers/net/mlx5/mlx5_ethdev.c:26:
../drivers/net/mlx5/mlx5_rx.h: In function ‘mprq_buf_replace’:
../drivers/net/mlx5/mlx5_rx.h:448:39: warning: declaration of ‘rep’ shadows a
previous local [-Wshadow]
  448 |                 struct mlx5_mprq_buf *rep;
      |                                       ^~~
../drivers/net/mlx5/mlx5_rx.h:424:31: note: shadowed declaration is here
  424 |         struct mlx5_mprq_buf *rep = rxq->mprq_repl;
      |                               ^~~
In file included from ../lib/eal/include/dev_driver.h:8,
                 from ../lib/ethdev/ethdev_driver.h:19,
                 from ../drivers/net/mlx5/mlx5_ethdev.c:13:
../drivers/net/mlx5/mlx5_tx.h: In function ‘mlx5_tx_burst_empw_inline’:
../lib/eal/include/rte_common.h:817:28: warning: declaration of ‘_a’ shadows a
previous local [-Wshadow]
  817 |                 typeof (a) _a = (a); \
      |                            ^~
../lib/eal/include/rte_common.h:798:25: note: in definition of macro ‘RTE_MIN’
  798 |                 typeof (b) _b = (b); \
      |                         ^
../drivers/net/mlx5/mlx5_tx.h:2971:40: note: in expansion of macro ‘RTE_MAX’
 2971 |                                        RTE_MAX(txq->inlen_empw +
      |                                        ^~~~~~~
../lib/eal/include/rte_common.h:797:28: note: shadowed declaration is here
  797 |                 typeof (a) _a = (a); \
      |                            ^~
../drivers/net/mlx5/mlx5_tx.h:2970:32: note: in expansion of macro ‘RTE_MIN’
 2970 |                         room = RTE_MIN(room,
      |                                ^~~~~~~
../lib/eal/include/rte_common.h:817:28: warning: declaration of ‘_a’ shadows a
previous local [-Wshadow]
  817 |                 typeof (a) _a = (a); \
      |                            ^~
../lib/eal/include/rte_common.h:798:34: note: in definition of macro ‘RTE_MIN’
  798 |                 typeof (b) _b = (b); \
      |                                  ^
../drivers/net/mlx5/mlx5_tx.h:2971:40: note: in expansion of macro ‘RTE_MAX’
 2971 |                                        RTE_MAX(txq->inlen_empw +
      |                                        ^~~~~~~
../lib/eal/include/rte_common.h:797:28: note: shadowed declaration is here
  797 |                 typeof (a) _a = (a); \
      |                            ^~
../drivers/net/mlx5/mlx5_tx.h:2970:32: note: in expansion of macro ‘RTE_MIN’
 2970 |                         room = RTE_MIN(room,
      |                                ^~~~~~~
../lib/eal/include/rte_common.h:818:28: warning: declaration of ‘_b’ shadows a
previous local [-Wshadow]
  818 |                 typeof (b) _b = (b); \
      |                            ^~
../lib/eal/include/rte_common.h:798:34: note: in definition of macro ‘RTE_MIN’
  798 |                 typeof (b) _b = (b); \
      |                                  ^
../drivers/net/mlx5/mlx5_tx.h:2971:40: note: in expansion of macro ‘RTE_MAX’
 2971 |                                        RTE_MAX(txq->inlen_empw +
      |                                        ^~~~~~~
../lib/eal/include/rte_common.h:798:28: note: shadowed declaration is here
  798 |                 typeof (b) _b = (b); \
      |                            ^~
../drivers/net/mlx5/mlx5_tx.h:2970:32: note: in expansion of macro ‘RTE_MIN’
 2970 |                         room = RTE_MIN(room,
      |                                ^~~~~~~

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Truncated because bugzilla can't take all of it.