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>
diff --git a/arch/mips/math-emu/sp_sqrt.c b/arch/mips/math-emu/sp_sqrt.c
index 94f5bef..b7c098a 100644
--- a/arch/mips/math-emu/sp_sqrt.c
+++ b/arch/mips/math-emu/sp_sqrt.c
@@ -100,10 +100,10 @@
 	if (ix != 0) {
 		ieee754_setcx(IEEE754_INEXACT);
 		switch (ieee754_csr.rm) {
-		case IEEE754_RU:
+		case FPU_CSR_RU:
 			q += 2;
 			break;
-		case IEEE754_RN:
+		case FPU_CSR_RN:
 			q += (q & 1);
 			break;
 		}