target-mips: Add missing calls to synchronise SoftFloat status

Add missing calls to synchronise the SoftFloat status with the CP1.FSCR:

+ for the rounding and flush-to-zero modes upon processor reset,

+ for the flush-to-zero mode on FSCR updates through the GDB stub.

Refactor code accordingly and remove the redundant RESTORE_ROUNDING_MODE
macro.

Signed-off-by: Thomas Schwinge <thomas@codesourcery.com>
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
diff --git a/target-mips/cpu.h b/target-mips/cpu.h
index f8cf143..8875c97 100644
--- a/target-mips/cpu.h
+++ b/target-mips/cpu.h
@@ -777,6 +777,18 @@
 extern unsigned int ieee_rm[];
 int ieee_ex_to_mips(int xcpt);
 
+static inline void restore_rounding_mode(CPUMIPSState *env)
+{
+    set_float_rounding_mode(ieee_rm[env->active_fpu.fcr31 & 3],
+                            &env->active_fpu.fp_status);
+}
+
+static inline void restore_flush_mode(CPUMIPSState *env)
+{
+    set_flush_to_zero((env->active_fpu.fcr31 & (1 << 24)) != 0,
+                      &env->active_fpu.fp_status);
+}
+
 static inline void cpu_get_tb_cpu_state(CPUMIPSState *env, target_ulong *pc,
                                         target_ulong *cs_base, int *flags)
 {