pgbuildfarm - client-code: fix varname typo fix failure where parent

Log Message:
-----------

fix varname typo

fix failure where parent of ccache dir does not exist - ccache will only
build the last segment, so we call mkpath on the whole thing.

Modified Files:
--------------
client-code:
run_build.pl (r1.23 -> r1.24)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbuildfarm/client-code/run_build.pl.diff?r1=1.23&r2=1.24)