PPC: Skip regress-740784 test on sim run

Takes too long on bots to run

Bug: 
Change-Id: Ia99717fe943ff6437497425abd3a3cb9999d7564
Reviewed-on: https://chromium-review.googlesource.com/746533Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#49055}

test/mjsunit/mjsunit.status

@@ -602,7 +602,7 @@
 
   # take too long with the simulator.
   'regress/regress-1132': [SKIP],
-  'regress/regress-740784': [PASS, SLOW],
+  'regress/regress-740784': [SKIP],
   'regress/regress-91008': [PASS, SLOW],
   'regress/regress-1257': [PASS, SLOW],
   'harmony/regexp-property-lu-ui': [PASS, SLOW],