fortran: Support clobbering of ASSOCIATE variables [PR41453]

fortran: Support clobbering of ASSOCIATE variables [PR41453]

This is in spirit a revert of:
r9-3051-gc109362313623d83fe0a5194bceaf994cf0c6ce0

That commit added a condition to avoid generating ICE with clobbers
of ASSOCIATE variables.
The test added at that point continues to pass if we remove that
condition now.

	PR fortran/41453
	PR fortran/87401

gcc/fortran/ChangeLog:

	* trans-expr.cc (gfc_conv_procedure_call): Remove condition
	disabling clobber generation for ASSOCIATE variables.

gcc/testsuite/ChangeLog:

	* gfortran.dg/intent_optimize_8.f90: New test.