powerpc/pkey: Define functions as static

Sparse tool is showing some warnings on pkeys.c file, mainly related to
storage class identifiers. There are static variables and functions not
declared as such. The same thing happens with an extern function, which
misses the header inclusion.

	arch/powerpc/mm/pkeys.c:14:6: warning: symbol 'pkey_execute_disable_supported' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:16:6: warning: symbol 'pkeys_devtree_defined' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:19:6: warning: symbol 'pkey_amr_mask' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:20:6: warning: symbol 'pkey_iamr_mask' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:21:6: warning: symbol 'pkey_uamor_mask' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:22:6: warning: symbol 'execute_only_key' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:60:5: warning: symbol 'pkey_initialize' was not declared. Should it be static?
	arch/powerpc/mm/pkeys.c:404:6: warning: symbol 'arch_vma_access_permitted' was not declared. Should it be static?

This patch fix al the warning, basically turning all global variables that
are not declared as extern at asm/pkeys.h into static.

It also includes asm/mmu_context.h header, which contains the definition of
arch_vma_access_permitted.
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/pkeys.c

@@ -6,20 +6,21 @@
  */
 
 #include <asm/mman.h>
+#include <asm/mmu_context.h>
 #include <asm/setup.h>
 #include <linux/pkeys.h>
 #include <linux/of_device.h>
 
 DEFINE_STATIC_KEY_TRUE(pkey_disabled);
-bool pkey_execute_disable_supported;
 int  pkeys_total;		/* Total pkeys as per device tree */
-bool pkeys_devtree_defined;	/* pkey property exported by device tree */
 u32  initial_allocation_mask;   /* Bits set for the initially allocated keys */
 u32  reserved_allocation_mask;  /* Bits set for reserved keys */
-u64  pkey_amr_mask;		/* Bits in AMR not to be touched */
-u64  pkey_iamr_mask;		/* Bits in AMR not to be touched */
-u64  pkey_uamor_mask;		/* Bits in UMOR not to be touched */
-int  execute_only_key = 2;
+static bool pkey_execute_disable_supported;
+static bool pkeys_devtree_defined;	/* property exported by device tree */
+static u64 pkey_amr_mask;		/* Bits in AMR not to be touched */
+static u64 pkey_iamr_mask;		/* Bits in AMR not to be touched */
+static u64 pkey_uamor_mask;		/* Bits in UMOR not to be touched */
+static int execute_only_key = 2;
 
 #define AMR_BITS_PER_PKEY 2
 #define AMR_RD_BIT 0x1UL
@@ -57,7 +58,7 @@ static inline bool pkey_mmu_enabled(void)
 		return cpu_has_feature(CPU_FTR_PKEY);
 }
 
-int pkey_initialize(void)
+static int pkey_initialize(void)
 {
 	int os_reserved, i;