Force dtype=float for array returned by inf_like
Force dtype=float for array returned by inf_like

The scalar case already explicity returned np.inf.

lpsinger/astropy,StuartLittlefair/astropy,dhomeier/astropy,saimn/astropy,lpsinger/astropy,saimn/astropy,aleksandr-bakanov/astropy,stargaser/astropy,dhomeier/astropy,dhomeier/astropy,saimn/astropy,pllim/astropy,mhvk/astropy,funbaker/astropy,StuartLittlefair/astropy,astropy/astropy,larrybradley/astropy,MSeifert04/astropy,larrybradley/astropy,pllim/astropy,dhomeier/astropy,pllim/astropy,astropy/astropy,DougBurke/astropy,bsipocz/astropy,larrybradley/astropy,dhomeier/astropy,MSeifert04/astropy,mhvk/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,mhvk/astropy,funbaker/astropy,MSeifert04/astropy,lpsinger/astropy,larrybradley/astropy,stargaser/astropy,funbaker/astropy,DougBurke/astropy,lpsinger/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,saimn/astropy,bsipocz/astropy,pllim/astropy,astropy/astropy,funbaker/astropy,astropy/astropy,DougBurke/astropy,mhvk/astropy,pllim/astropy,bsipocz/astropy,bsipocz/astropy,lpsinger/astropy,DougBurke/astropy,astropy/astropy,stargaser/astropy,aleksandr-bakanov/astropy,MSeifert04/astropy,aleksandr-bakanov/astropy,stargaser/astropy,mhvk/astropy,saimn/astropy,StuartLittlefair/astropy