powerpc/mm: fix erroneous duplicate slb_addr_limit init

Commit 67fda38f0d ("powerpc/mm: Move slb_addr_linit to
early_init_mmu") moved slb_addr_limit init out of setup_arch().

Commit 701101865f ("powerpc/mm: Reduce memory usage for mm_context_t
for radix") brought it back into setup_arch() by error.

This patch reverts that erroneous regress.

Fixes: 701101865f ("powerpc/mm: Reduce memory usage for mm_context_t for radix")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/setup-common.c

@@ -950,12 +950,6 @@ void __init setup_arch(char **cmdline_p)
 	init_mm.end_data = (unsigned long) _edata;
 	init_mm.brk = klimit;
 
-#ifdef CONFIG_PPC_MM_SLICES
-#if defined(CONFIG_PPC_8xx)
-	init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
-#endif
-#endif
-
 #ifdef CONFIG_SPAPR_TCE_IOMMU
 	mm_iommu_init(&init_mm);
 #endif