lib/repo.c: fix two memleaks in error paths found by clang.
lib/repo.c: fix two memleaks in error paths found by clang.

ebfe/xbps,datenwolf/xbps,stpx/xbps,stpx/xbps,ebfe/xbps,datenwolf/xbps,datenwolf/xbps,stpx/xbps,ebfe/xbps