powerpc/process: Remove unneccessary #ifdef CONFIG_PPC64 in copy_thread_tls()

is_32bit_task() exists on both PPC64 and PPC32, no need of an ifdefery.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6ecbda05b4119c40222dc8ec284604e1597c9bff.1580327381.git.christophe.leroy@c-s.fr

arch/powerpc/kernel/process.c

@@ -1634,11 +1634,9 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
 		p->thread.regs = childregs;
 		childregs->gpr[3] = 0;  /* Result from fork() */
 		if (clone_flags & CLONE_SETTLS) {
-#ifdef CONFIG_PPC64
 			if (!is_32bit_task())
 				childregs->gpr[13] = tls;
 			else
-#endif
 				childregs->gpr[2] = tls;
 		}