MIPS: math-emu: Switch to using the MIPS rounding modes.

Previously math-emu was using the IEEE-754 constants internally.  These
were differing by having the constants for rounding to +/- infinity
switched, so a conversion was necessary.  This would be entirely
avoidable if the MIPS constants were used throughout, so get rid of
the bloat.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/math-emu/ieee754.h

@@ -126,13 +126,6 @@ enum {
 #define IEEE754_CGT	0x04
 #define IEEE754_CUN	0x08
 
-/* rounding mode
-*/
-#define IEEE754_RN	0	/* round to nearest */
-#define IEEE754_RZ	1	/* round toward zero  */
-#define IEEE754_RD	2	/* round toward -Infinity */
-#define IEEE754_RU	3	/* round toward +Infinity */
-
 /* "normal" comparisons
 */
 static inline int ieee754sp_eq(union ieee754sp x, union ieee754sp y)