powerpc/mm/hash: Remove unnecessary do { } while(0) loop

Avoid coverity false warnings like:

  *** CID 187347:  Control flow issues  (UNREACHABLE)
  /arch/powerpc/mm/hash_native_64.c: 819 in native_flush_hash_range()
  813        slot += hidx & _PTEIDX_GROUP_IX;
  814        hptep = htab_address + slot;
  815        want_v = hpte_encode_avpn(vpn, psize, ssize);
  816        hpte_v = hpte_get_old_v(hptep);
  817
  818        if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))
  >>>     CID 187347:  Control flow issues  (UNREACHABLE)
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/book3s/64/hash-64k.h

@@ -137,10 +137,9 @@ extern bool __rpte_sub_valid(real_pte_t rpte, unsigned long index);
 		shift = mmu_psize_defs[psize].shift;			\
 		for (index = 0; vpn < __end; index++,			\
 			     vpn += (1L << (shift - VPN_SHIFT))) {	\
-			if (!__split || __rpte_sub_valid(rpte, index))	\
-				do {
+		if (!__split || __rpte_sub_valid(rpte, index))
 
-#define pte_iterate_hashed_end() } while(0); } } while(0)
+#define pte_iterate_hashed_end()  } } while(0)
 
 #define pte_pagesize_index(mm, addr, pte)	\
 	(((pte) & H_PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K)