parisc: Use max() to calculate parisc_tlb_flush_threshold

Use max() to reduce 4 lines of code to a single line and improve its
readability.

Fixes the following Coccinelle/coccicheck warning reported by
minmax.cocci:

  WARNING opportunity for max()
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/kernel/cache.c

@@ -611,11 +611,7 @@ void __init parisc_setup_cache_timing(void)
 		threshold/1024);
 
 set_tlb_threshold:
-	if (threshold > FLUSH_TLB_THRESHOLD)
-		parisc_tlb_flush_threshold = threshold;
-	else
-		parisc_tlb_flush_threshold = FLUSH_TLB_THRESHOLD;
-
+	parisc_tlb_flush_threshold = max(threshold, FLUSH_TLB_THRESHOLD);
 	printk(KERN_INFO "TLB flush threshold set to %lu KiB\n",
 		parisc_tlb_flush_threshold/1024);
 }