[MERGE #6045 @LouisLaf] Small FG peeps improvement
[MERGE #6045 @LouisLaf] Small FG peeps improvement

Merge pull request #6045 from LouisLaf:fgpeeps

Branch to next instr wasn't catching the case where this is an uncoalesced label in the way.  This triggered an assert in the globopt (issue #5953) which did rely onthe peep to kick in.  Fixed it by skipping over labels.

Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore