gdb/aarch64: Use type_align instead of aarch64_type_align

gdb/aarch64: Use type_align instead of aarch64_type_align

Replaces use of aarch64_type_align with common type_align function.

Doing this fixes a bug in aarch64_type_align where static fields are
considered as part of the alignment calculation of a struct, which
results in arguments passed on the stack being misaligned.  This bug
is exposed in the new test gdb.cp/many-args.exp.

Part of the old aarch64_type_align is retained and used as the gdbarch
type align callback in order to correctly align vectors.

gdb/ChangeLog:

	* aarch64-tdep.c (aarch64_type_align): Only handle vector override
	case.
	(pass_on_stack): Use type_align.
	(aarch64_gdbarch_init): Register aarch64_type_align gdbarch
	function.

gdb/testsuite/ChangeLog:

	* gdb.cp/many-args.cc: New file.
	* gdb.cp/many-args.exp: New file.