x86/platform/uv: Remove extra parentheses

Remove extra parentheses to fix the extraneous parentheses clang
warning.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180520080012.8215-1-rvarsha016@gmail.com

arch/x86/platform/uv/tlb_uv.c

@@ -615,7 +615,7 @@ static int uv2_3_wait_completion(struct bau_desc *bau_desc,
 
 	/* spin on the status MMR, waiting for it to go idle */
 	while (descriptor_stat != UV2H_DESC_IDLE) {
-		if ((descriptor_stat == UV2H_DESC_SOURCE_TIMEOUT)) {
+		if (descriptor_stat == UV2H_DESC_SOURCE_TIMEOUT) {
 			/*
 			 * A h/w bug on the destination side may
 			 * have prevented the message being marked