Change Cvar_Cycle_f to use Q_atof to be consistent with other cvar code. Q_atof("0.3"), a float, does not == atof("0.3"), a double.
Fixes "cycle r_wateralpha 0.3 0.6 1" not working reported by AAS.

git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk@969 af15c1b1-3010-417e-b628-4374ebc0bcbd