[PATCH v2 1/1] rtla: fix missing unistd include

[Andreas Ziegler <br025@umbiko.net>]

Compiling RTLA 7.1.x with GCC 16 and uClibc as standard library fails
with these errors:

src/common.c: In function ‘set_signals’:
src/common.c:40:17: error: implicit declaration of function ‘alarm’ [-Wimplicit-function-declaration]
   40 |                 alarm(params->duration);
      |                 ^~~~~
src/common.c: In function ‘common_apply_config’:
src/common.c:187:44: error: implicit declaration of function ‘getpid’; did you mean ‘getpt’? [-Wimplicit-function-declaration]
  187 |                 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
      |                                            ^~~~~~
      |                                            getpt
In file included from src/common.c:9:
src/common.c: In function ‘run_tool’:
src/common.c:262:19: error: implicit declaration of function ‘sysconf’; did you mean ‘sscanf’? [-Wimplicit-function-declaration]
  262 |         nr_cpus = get_nprocs_conf();
      |                   ^~~~~~~~~~~~~~~
src/common.c:262:19: error: ‘_SC_NPROCESSORS_CONF’ undeclared (first use in this function)
  262 |         nr_cpus = get_nprocs_conf();
      |                   ^~~~~~~~~~~~~~~
src/common.c:262:19: note: each undeclared identifier is reported only once for each function it appears in
src/common.c:370:17: error: implicit declaration of function ‘sleep’ [-Wimplicit-function-declaration]
  370 |                 sleep(1);
      |                 ^~~~~

Restore the missing unistd.h include.

Fixes: 115b06a00875 ("tools/rtla: Consolidate nr_cpus usage across all tools")

Signed-off-by: Andreas Ziegler <br025@umbiko.net>
---
Changes v1 -> v2:
  adapt commit message
  correct fixes: formatting
  rebase on current master (502d801f0ab0)

 tools/tracing/rtla/src/common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/tracing/rtla/src/common.c b/tools/tracing/rtla/src/common.c
index d0a8a6edbf0c..8c7f5e75b2ec 100644
--- a/tools/tracing/rtla/src/common.c
+++ b/tools/tracing/rtla/src/common.c
@@ -5,6 +5,7 @@
 #include <signal.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <sys/sysinfo.h>
 
 #include "common.h"
-- 
2.53.0