sh: implement flush_icache_user_range

The SuperH implementation of flush_icache_range seems to be able to cope
with user addresses.  Just define flush_icache_user_range to
flush_icache_range.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Link: http://lkml.kernel.org/r/20200515143646.3857579-22-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/sh/include/asm/cacheflush.h

@@ -46,6 +46,7 @@ extern void flush_cache_range(struct vm_area_struct *vma,
 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *page);
 extern void flush_icache_range(unsigned long start, unsigned long end);
+#define flush_icache_user_range flush_icache_range
 extern void flush_icache_page(struct vm_area_struct *vma,
 				 struct page *page);
 extern void flush_cache_sigtramp(unsigned long address);