cputlb: drop flush_global flag from tlb_flush

We have never has the concept of global TLB entries which would avoid
the flush so we never actually use this flag. Drop it and make clear
that tlb_flush is the sledge-hammer it has always been.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[DG: ppc portions]
Acked-by: David Gibson <david@gibson.dropbear.id.au>

target/i386/misc_helper.c

@@ -635,5 +635,5 @@ void helper_wrpkru(CPUX86State *env, uint32_t ecx, uint64_t val)
     }
 
     env->pkru = val;
-    tlb_flush(cs, 1);
+    tlb_flush(cs);
 }