[PATCH] btrfs: handle -Wmaybe-uninitialized with clang

[Tom Rix <trix@redhat.com>]

The clang build reports this error
error: unknown warning option '-Wmaybe-uninitialized'; did you mean '-Wuninitialized'? [-Werror,-Wunknown-warning-option]
make[3]: *** [scripts/Makefile.build:252: fs/btrfs/super.o] Error 1

-Wmaybe-uninitialized is a gcc only flag.  Move to setting with cc-option.

Fixes: 1b19c4c249a1 ("btrfs: turn on -Wmaybe-uninitialized")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 fs/btrfs/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index eca995abccdf..460eced3f5bd 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -7,12 +7,12 @@ subdir-ccflags-y += -Wmissing-format-attribute
 subdir-ccflags-y += -Wmissing-prototypes
 subdir-ccflags-y += -Wold-style-definition
 subdir-ccflags-y += -Wmissing-include-dirs
-subdir-ccflags-y += -Wmaybe-uninitialized
 condflags := \
 	$(call cc-option, -Wunused-but-set-variable)		\
 	$(call cc-option, -Wunused-const-variable)		\
 	$(call cc-option, -Wpacked-not-aligned)			\
-	$(call cc-option, -Wstringop-truncation)
+	$(call cc-option, -Wstringop-truncation)		\
+	$(call cc-option, -Wmaybe-uninitialized)
 subdir-ccflags-y += $(condflags)
 # The following turn off the warnings enabled by -Wextra
 subdir-ccflags-y += -Wno-missing-field-initializers
-- 
2.27.0