powerpc/irq: Remove arch_local_irq_restore() for !CONFIG_CC_HAS_ASM_GOTO

All supported versions of GCC & clang support asm goto.

Remove the !CONFIG_CC_HAS_ASM_GOTO version of arch_local_irq_restore()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/58df50c9e77e2ed945bacdead30412770578886b.1652715336.git.christophe.leroy@csgroup.eu