[PR testsuite/114182] Fix minor testsuite issue when double == float

This is a minor testsuite adjustment

attr-complex-method-2.c selects between two scan-tree-dump clauses based on
avr, !avr.  But what they really should be checking is "large_double" that way
it works for avr, h8, rl78 and any other target which makes doubles the same
size as floats.

attr-complex-method.c should be doing the same thing.

After this change avr passes attr-complex-method.c and the rl78 and h8 ports
will pass both tests.  Other targets in my tester are unaffected.

	PR testsuite/114182

gcc/testsuite/

	* gcc.c-torture/compile/attr-complex-method.c: Use
	"large_double" to select between scan outputs.
	* gcc.c-torture/compile/attr-complex-method-2.c: Similarly.