mips/mathops: remove 64-bit code

GCC is perfectly happy generating optimized multiplication code on its own for
64-bit arches. GCC refuses to optimize the loongson code when in 32-bit mode,
so I've left that.
Signed-off-by: James Cowgill <james410@cowgill.org.uk>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/mips/mathops.h

@@ -49,32 +49,6 @@ static inline av_const int64_t MLS64(int64_t d, int a, int b)
 }
 #define MLS64(d, a, b) ((d) = MLS64(d, a, b))
 
-#elif ARCH_MIPS64
-
-static inline av_const int64_t MAC64(int64_t d, int a, int b)
-{
-    int64_t m;
-    __asm__ ("dmult %2, %3     \n\t"
-             "mflo  %1         \n\t"
-             "daddu %0, %0, %1 \n\t"
-             : "+r"(d), "=&r"(m) : "r"(a), "r"(b)
-             : "hi", "lo");
-    return d;
-}
-#define MAC64(d, a, b) ((d) = MAC64(d, a, b))
-
-static inline av_const int64_t MLS64(int64_t d, int a, int b)
-{
-    int64_t m;
-    __asm__ ("dmult %2, %3     \n\t"
-             "mflo  %1         \n\t"
-             "dsubu %0, %0, %1 \n\t"
-             : "+r"(d), "=&r"(m) : "r"(a), "r"(b)
-             : "hi", "lo");
-    return d;
-}
-#define MLS64(d, a, b) ((d) = MLS64(d, a, b))
-
 #endif
 
 #endif /* HAVE_INLINE_ASM */