rename div64_64 to div64_u64

Rename div64_64 to div64_u64 to make it consistent with the other divide
functions, so it clearly includes the type of the divide.  Move its definition
to math64.h as currently no architecture overrides the generic implementation.
 They can still override it of course, but the duplicated declarations are
avoided.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/math64.h b/include/linux/math64.h
index 6d17166..c1a5f81 100644
--- a/include/linux/math64.h
+++ b/include/linux/math64.h
@@ -27,6 +27,14 @@
 	return dividend / divisor;
 }
 
+/**
+ * div64_u64 - unsigned 64bit divide with 64bit divisor
+ */
+static inline u64 div64_u64(u64 dividend, u64 divisor)
+{
+	return dividend / divisor;
+}
+
 #elif BITS_PER_LONG == 32
 
 #ifndef div_u64_rem
@@ -41,6 +49,10 @@
 extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
 #endif
 
+#ifndef div64_u64
+extern u64 div64_u64(u64 dividend, u64 divisor);
+#endif
+
 #endif /* BITS_PER_LONG */
 
 /**