ARM: 6382/1: Remove superfluous flush_kernel_dcache_page()

Since page cache pages are now considered 'dirty' by default, the cache
flushing is handled via __flush_dcache_page() when a page gets mapped to
user space. Highmem pages on VIVT systems are flushed during kunmap()
and flush_kernel_dcache_page() was already a no-op in this case.

ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE is still defined since ARM needs
specific implementations for flush_kernel_vmap_range() and
invalidate_kernel_vmap_range().

Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/include/asm/cacheflush.h

@@ -405,9 +405,6 @@ static inline void flush_anon_page(struct vm_area_struct *vma,
 #define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
 static inline void flush_kernel_dcache_page(struct page *page)
 {
-	/* highmem pages are always flushed upon kunmap already */
-	if ((cache_is_vivt() || cache_is_vipt_aliasing()) && !PageHighMem(page))
-		__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
 }
 
 #define flush_dcache_mmap_lock(mapping) \