ARM: 9468/1: fix memset64() on big-endian

On big-endian systems the 32-bit low and high halves need to be swapped
for the underlying assembly implementation to work correctly.

Fixes: fd1d362600 ("ARM: implement memset32 & memset64")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

arch/arm/include/asm/string.h

@@ -42,7 +42,10 @@ static inline void *memset32(uint32_t *p, uint32_t v, __kernel_size_t n)
 extern void *__memset64(uint64_t *, uint32_t low, __kernel_size_t, uint32_t hi);
 static inline void *memset64(uint64_t *p, uint64_t v, __kernel_size_t n)
 {
-	return __memset64(p, v, n * 8, v >> 32);
+	if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
+		return __memset64(p, v, n * 8, v >> 32);
+	else
+		return __memset64(p, v >> 32, n * 8, v);
 }
 
 /*