sh: Use generic GCC library routines

The C implementations of __ashldi3(), __ashrdi3__(), and __lshrdi3() in
arch/sh/lib/ are identical to the generic C implementations in lib/.
Reduce duplication by switching SH to the generic versions.

Update the include path in arch/sh/boot/compressed accordingly.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/74dbe68dc8e2ffb6180092f73723fe21ab692c7a.1679566500.git.geert+renesas@glider.be


Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>