powerpc: Prefer __section and __printf from compiler_attributes.h

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
[mpe: Drop changes to a/p/boot which doesn't use linux headers]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190812215052.71840-10-ndesaulniers@google.com

arch/powerpc/include/asm/cache.h

@@ -97,7 +97,7 @@ static inline u32 l1_icache_bytes(void)
 
 #endif
 
-#define __read_mostly __attribute__((__section__(".data..read_mostly")))
+#define __read_mostly __section(.data..read_mostly)
 
 #ifdef CONFIG_PPC_BOOK3S_32
 extern long _get_L2CR(void);

arch/powerpc/kernel/btext.c

@@ -26,7 +26,7 @@
 static void scrollscreen(void);
 #endif
 
-#define __force_data __attribute__((__section__(".data")))
+#define __force_data __section(.data)
 
 static int g_loc_X __force_data;
 static int g_loc_Y __force_data;