ICF: Remove unneeded check for CASE_LABEL_EXPR

ICF: Remove unneeded check for CASE_LABEL_EXPR

I noticed there was a check to see gimple_switch_label
returns a CASE_LABEL_EXPR after already using CASE_LOW/CASE_HIGH
on the same value.

This removes the check as it is always true.

Bootstrapped and tested on x86_64-linux-gnu.

gcc/ChangeLog:

	* ipa-icf-gimple.cc (func_checker::compare_gimple_switch): Remove
	the check on CASE_LABEL_EXPR since it is redundant.

Signed-off-by: Andrew Pinski <andrew.pinski@oss.qualcomm.com>