powerpc/32s: Don't hash_preload() kernel text

We now always map kernel text with BATs. Neither need to preload
hash with kernel text addresses nor ensure they are never evicted.

This is more or less a revert of commit ee4f2ea48674 ("[POWERPC] Fix
32-bit mm operations when not using BATs")

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0a0bab7fadd89aa829e33420fbc10d60c59040a7.1606285014.git.christophe.leroy@csgroup.eu
diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index 5c60dca..23f60e9 100644
--- a/arch/powerpc/mm/book3s32/mmu.c
+++ b/arch/powerpc/mm/book3s32/mmu.c
@@ -302,7 +302,7 @@ void __init setbat(int index, unsigned long virt, phys_addr_t phys,
 /*
  * Preload a translation in the hash table
  */
-void hash_preload(struct mm_struct *mm, unsigned long ea)
+static void hash_preload(struct mm_struct *mm, unsigned long ea)
 {
 	pmd_t *pmd;