[ARM] 2939/1: Fix compilation error in arch/arm/mm/flush.c

Patch from Catalin Marinas

When CONFIG_CPU_CACHE_VIPT is defined, the flush_pfn_alias() function is
implicitely declared and it later conflicts with its actual definition.
This patch moves the function definition to the beginning of the file.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/flush.c

@@ -17,6 +17,24 @@
 
 #ifdef CONFIG_CPU_CACHE_VIPT
 
+#define ALIAS_FLUSH_START	0xffff4000
+
+#define TOP_PTE(x)	pte_offset_kernel(top_pmd, x)
+
+static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr)
+{
+	unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT);
+
+	set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL));
+	flush_tlb_kernel_page(to);
+
+	asm(	"mcrr	p15, 0, %1, %0, c14\n"
+	"	mcrr	p15, 0, %1, %0, c5\n"
+	    :
+	    : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES)
+	    : "cc");
+}
+
 void flush_cache_mm(struct mm_struct *mm)
 {
 	if (cache_is_vivt()) {
@@ -67,24 +85,6 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsig
 	if (cache_is_vipt_aliasing())
 		flush_pfn_alias(pfn, user_addr);
 }
-
-#define ALIAS_FLUSH_START	0xffff4000
-
-#define TOP_PTE(x)	pte_offset_kernel(top_pmd, x)
-
-static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr)
-{
-	unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT);
-
-	set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL));
-	flush_tlb_kernel_page(to);
-
-	asm(	"mcrr	p15, 0, %1, %0, c14\n"
-	"	mcrr	p15, 0, %1, %0, c5\n"
-	    :
-	    : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES)
-	    : "cc");
-}
 #else
 #define flush_pfn_alias(pfn,vaddr)	do { } while (0)
 #endif