DSE: Support triming of some more memset [PR87901]

DSE: Support triming of some more memset [PR87901]

DSE has support for trimming memset (and memset like) statements.
In this case we have `MEM <unsigned char[17]> [(char * {ref-all})&z] = {};` in
the IR and when we go to trim it, we call build_fold_addr_expr which leaves around
a cast from one pointer type to another. This is due to build_fold_addr_expr
being generic but in gimple you don't need these casts.

	PR tree-optimization/87901

gcc/ChangeLog:

	* tree-ssa-dse.cc (maybe_trim_constructor_store): Strip over useless type
	conversions after taking the address of the MEM_REF.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/ssa-dse-52.c: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>