Add 'static' to please Sparse

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c
index 194414c..d3dab33 100644
--- a/target-mips/op_helper.c
+++ b/target-mips/op_helper.c
@@ -1868,7 +1868,7 @@
 #define FLOAT_SNAN64 0x7fffffffffffffffULL
 
 /* convert MIPS rounding mode in FCR31 to IEEE library */
-unsigned int ieee_rm[] = {
+static unsigned int ieee_rm[] = {
     float_round_nearest_even,
     float_round_to_zero,
     float_round_up,