Fix wrong array type conversion with different storage orde
When two arrays of scalars have a different storage order in Ada, the
front-end makes sure that the conversion is performed component-wise
so that each component can be reversed. So it's a little bit counter
productive that the ldist pass performs the opposite transformation
and synthesizes a memcpy/memmove in this case.
gcc/
* tree-loop-distribution.cc (loop_distribution::classify_builtin_ldst):
Bail out if source and destination do not have the same storage order.
gcc/testsuite/
* gnat.dg/sso18.adb: New test.