powerpc: Simplify strict_kernel_rwx_enabled()

Now that rodata_enabled is always declared, remove #ifdef
and define a single version of strict_kernel_rwx_enabled().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

arch/powerpc/include/asm/mmu.h

@@ -330,17 +330,10 @@ static __always_inline bool early_radix_enabled(void)
 	return early_mmu_has_feature(MMU_FTR_TYPE_RADIX);
 }
 
-#ifdef CONFIG_STRICT_KERNEL_RWX
 static inline bool strict_kernel_rwx_enabled(void)
 {
-	return rodata_enabled;
+	return IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && rodata_enabled;
 }
-#else
-static inline bool strict_kernel_rwx_enabled(void)
-{
-	return false;
-}
-#endif
 
 static inline bool strict_module_rwx_enabled(void)
 {