SCRAMV1: add BuildRequires on gmake

gmake must be used from CMSDIST as it's not required or/and provided
on the target system.

Signed-off-by: David Abdurachmanov <davidlt@cern.ch>
Merge pull request #1155 from smuzaffar/IB/CMSSW_5_3_X/slc6_amd64_gcc472

SCRAMV1: add BuildRequires on gmake