media: staging: atomisp: disable warnings with cc-disable-warning

Instead of directly using -Wno-foo, use cc-disable-warning, as it
checks if the compiler has the warnings we want to disable.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/drivers/staging/media/atomisp/pci/atomisp2/Makefile b/drivers/staging/media/atomisp/pci/atomisp2/Makefile
index 726eaa2..2bd98f0 100644
--- a/drivers/staging/media/atomisp/pci/atomisp2/Makefile
+++ b/drivers/staging/media/atomisp/pci/atomisp2/Makefile
@@ -354,7 +354,9 @@
 
 # HACK! While this driver is in bad shape, don't enable several warnings
 #       that would be otherwise enabled with W=1
-ccflags-y += -Wno-unused-const-variable -Wno-missing-prototypes \
-	     -Wno-unused-but-set-variable -Wno-missing-declarations \
-	     -Wno-suggest-attribute=format -Wno-missing-prototypes \
-	     -Wno-implicit-fallthrough
+ccflags-y += $(call cc-disable-warning, implicit-fallthrough)
+ccflags-y += $(call cc-disable-warning, missing-prototypes)
+ccflags-y += $(call cc-disable-warning, missing-declarations)
+ccflags-y += $(call cc-disable-warning, suggest-attribute=format)
+ccflags-y += $(call cc-disable-warning, unused-const-variable)
+ccflags-y += $(call cc-disable-warning, unused-but-set-variable)