Prevent automake to inject -g -O2 if cflags isn't set
Prevent automake to inject -g -O2 if cflags isn't set

Change-Id: I048c0bb2e5c26a6565855acc2eca70d071dbb753
Reviewed-on: http://review.couchbase.org/19399
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>
Tested-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>

couchbase/libcouchbase,signmotion/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,mody/libcouchbase,mody/libcouchbase,kojiromike/libcouchbase,maxim-ky/libcouchbase,uvenum/libcouchbase,PureSwift/libcouchbase,trondn/libcouchbase,mnunberg/libcouchbase,kojiromike/libcouchbase,maxim-ky/libcouchbase,avsej/libcouchbase,mnunberg/libcouchbase,signmotion/libcouchbase,signmotion/libcouchbase,senthilkumaranb/libcouchbase,uvenum/libcouchbase,couchbase/libcouchbase,avsej/libcouchbase,mnunberg/libcouchbase,couchbase/libcouchbase,kojiromike/libcouchbase,avsej/libcouchbase,maxim-ky/libcouchbase,trondn/libcouchbase,trondn/libcouchbase,couchbase/libcouchbase,mody/libcouchbase,couchbase/libcouchbase,maxim-ky/libcouchbase,mody/libcouchbase,uvenum/libcouchbase,uvenum/libcouchbase,couchbase/libcouchbase,mnunberg/libcouchbase,PureSwift/libcouchbase,trondn/libcouchbase,PureSwift/libcouchbase,senthilkumaranb/libcouchbase,signmotion/libcouchbase,couchbase/libcouchbase,mnunberg/libcouchbase,senthilkumaranb/libcouchbase,kojiromike/libcouchbase,trondn/libcouchbase,senthilkumaranb/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,uvenum/libcouchbase,PureSwift/libcouchbase