AIX: Adding bbigtoc link step option to fix TOC overflow error

    Adding link option -bbigtoc to fix TOC overflow error.
    The option instructs the linker to generate TOC larger
    than 64k.

    TOC: http://www.ibm.com/developerworks/rational/library/overview-toc-aix/

R=machenbach@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2107513002
Cr-Commit-Position: refs/heads/master@{#37327}

gypfiles/toolchain.gypi

@@ -1097,7 +1097,7 @@
           }],
           [ 'v8_target_arch=="ppc64"', {
             'cflags': [ '-maix64' ],
-            'ldflags': [ '-maix64' ],
+            'ldflags': [ '-maix64 -Wl,-bbigtoc' ],
           }],
         ],
       }],