Bug 1314678 - Do not include mozconfig.cache in cross-mozconfig.common. r=mshal

It's already included by the nightly and debug mozconfigs which end up including
cross-mozconfig.common, including it again appears ineffectual and causes
failures in artifact builds.

MozReview-Commit-ID: 1DH4r8mgNXe

--HG--
extra : rebase_source : d01254a2140ad6fc90321c8a5d1f4c439e93f7b1

build/macosx/cross-mozconfig.common

@@ -51,6 +51,4 @@ if [ "x$MOZ_PKG_SPECIAL" != "xasan" ]; then
   ac_add_options --enable-clang-plugin
 fi
 
-. "$topsrcdir/build/mozconfig.cache"
-
 export SOCORRO_SYMBOL_UPLOAD_TOKEN_FILE=/builds/crash-stats-api.token