MIPS: Define ioremap_uc

All architectures must now define ioremap_uc(), but MIPS currently
only has ioremap_nocache().

Fixes: 4c73e892 ("arch/*/io.h: Add ioremap_uc() to all architectures")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11263/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/io.h

@@ -256,6 +256,7 @@ static inline void __iomem * __ioremap_mode(phys_addr_t offset, unsigned long si
  */
 #define ioremap_nocache(offset, size)					\
 	__ioremap_mode((offset), (size), _CACHE_UNCACHED)
+#define ioremap_uc ioremap_nocache
 
 /*
  * ioremap_cachable -	map bus memory into CPU space