[PR97504] riscv needs wraplf for aux_long_long_float too

[PR97504] riscv needs wraplf for aux_long_long_float too

riscv is another platform on which GNAT maps Long_Long_Float to double
rather than long double, so we have to explicitly avoid the long
double intrinsics.

for  gcc/ada/ChangeLog

	PR ada/97504
	* Makefile.rtl (LIBGNAT_TARGET_PAIRS> <riscv*-*-*>: Use wraplf
	version of Aux_Long_Long_Float.