Fix the branch information in .reviewboardrc for release-1.7.x.
Fix the branch information in .reviewboardrc for release-1.7.x.

The merge from master reset the branch information, causing post-review
on the branch to include changes made on release-1.7.x not yet on
master.

chipx86/reviewboard,1tush/reviewboard,1tush/reviewboard,1tush/reviewboard,davidt/reviewboard,KnowNo/reviewboard,davidt/reviewboard,brennie/reviewboard,bkochendorfer/reviewboard,reviewboard/reviewboard,beol/reviewboard,davidt/reviewboard,bkochendorfer/reviewboard,bkochendorfer/reviewboard,brennie/reviewboard,sgallagher/reviewboard,custode/reviewboard,KnowNo/reviewboard,custode/reviewboard,1tush/reviewboard,reviewboard/reviewboard,chipx86/reviewboard,beol/reviewboard,chipx86/reviewboard,sgallagher/reviewboard,beol/reviewboard,1tush/reviewboard,reviewboard/reviewboard,brennie/reviewboard,custode/reviewboard,custode/reviewboard,sgallagher/reviewboard,reviewboard/reviewboard,beol/reviewboard,KnowNo/reviewboard,brennie/reviewboard,sgallagher/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard,1tush/reviewboard,1tush/reviewboard,KnowNo/reviewboard,chipx86/reviewboard,1tush/reviewboard,davidt/reviewboard