arm64: drop unused __local_flush_icache_all()

After commit 65da0a8e34a8 ("arm64: use non-global mappings for UEFI
runtime regions"), nobody use __local_flush_icache_all() anymore,
so drop it.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/cacheflush.h

@@ -116,13 +116,6 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *);
 
-static inline void __local_flush_icache_all(void)
-{
-	asm("ic iallu");
-	dsb(nsh);
-	isb();
-}
-
 static inline void __flush_icache_all(void)
 {
 	asm("ic	ialluis");