analyzer: fix missing -Wanalyzer-use-of-uninitialized-value on special-cased function...

analyzer: fix missing -Wanalyzer-use-of-uninitialized-value on special-cased functions [PR106573]

We were missing checks for uninitialized params on calls to functions
that the analyzer has hardcoded knowledge of - both for those that are
handled just by state machines, and for those that are handled in
region-model-impl-calls.cc (for those arguments for which the svalue
wasn't accessed in handling the call).

Fixed thusly.

gcc/analyzer/ChangeLog:
	PR analyzer/106573
	* region-model.cc (region_model::on_call_pre): Ensure that we call
	get_arg_svalue on all arguments.

gcc/testsuite/ChangeLog:
	PR analyzer/106573
	* gcc.dg/analyzer/error-uninit.c: New test.
	* gcc.dg/analyzer/fd-uninit-1.c: New test.
	* gcc.dg/analyzer/file-uninit-1.c: New test.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>