X87: [test] disable number-tostring test case for x87.

test/mjsunit/mjsunit.status

Index: test/mjsunit/mjsunit.status
diff --git a/test/mjsunit/mjsunit.status b/test/mjsunit/mjsunit.status
index 009cb0132e5e806019f3c96ea8413cf268f2cda8..0fe87da3b20e64662e0a67d45d81fbc3cbe4e287 100644
--- a/test/mjsunit/mjsunit.status
+++ b/test/mjsunit/mjsunit.status
@@ -495,6 +495,12 @@
   'math-floor-of-div-minus-zero': [SKIP],
 }],  # 'arch == mips64el or arch == mips64'
 
+['arch == x87', {
+   # The result produced by Gcc on linux platform is extended 80-bit double
+   # precision and not the expected standard 64-bit double precision.
+   'number-tostring-big-integer': [SKIP],
+}],  # 'arch == x87'
+
 ##############################################################################
 ['system == windows', {
   # TODO(mstarzinger): Too slow with turbo fan.