openrisc: Use asm-generic's version of fix_to_virt() & virt_to_fix()

Openrisc's implementation of fix_to_virt() & virt_to_fix() share same
functionality with ones of asm generic.

Plus, generic version of fix_to_virt() can trap invalid index at compile
time.

Thus, Replace the arch-specific implementations with asm generic's ones.
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>

arch/openrisc/include/asm/fixmap.h

@@ -50,35 +50,6 @@ enum fixed_addresses {
 /* FIXADDR_BOTTOM might be a better name here... */
 #define FIXADDR_START		(FIXADDR_TOP - FIXADDR_SIZE)
 
-#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))
-#define __virt_to_fix(x)	((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
-
-/*
- * 'index to address' translation. If anyone tries to use the idx
- * directly without tranlation, we catch the bug with a NULL-deference
- * kernel oops. Illegal ranges of incoming indices are caught too.
- */
-static __always_inline unsigned long fix_to_virt(const unsigned int idx)
-{
-	/*
-	 * this branch gets completely eliminated after inlining,
-	 * except when someone tries to use fixaddr indices in an
-	 * illegal way. (such as mixing up address types or using
-	 * out-of-range indices).
-	 *
-	 * If it doesn't get removed, the linker will complain
-	 * loudly with a reasonably clear error message..
-	 */
-	if (idx >= __end_of_fixed_addresses)
-		BUG();
-
-	return __fix_to_virt(idx);
-}
-
-static inline unsigned long virt_to_fix(const unsigned long vaddr)
-{
-	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
-	return __virt_to_fix(vaddr);
-}
+#include <asm-generic/fixmap.h>
 
 #endif