powerpc: remove unneeded semicolon

Fix the following coccicheck warnings:

./arch/powerpc/kernel/prom_init.c:2986:2-3: Unneeded semicolon.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1614151761-53721-1-git-send-email-jiapeng.chong@linux.alibaba.com

arch/powerpc/kernel/prom_init.c

@@ -2983,7 +2983,7 @@ static void __init fixup_device_tree_efika_add_phy(void)
 				" 0x3 encode-int encode+"
 				" s\" interrupts\" property"
 			" finish-device");
-	};
+	}
 
 	/* Check for a PHY device node - if missing then create one and
 	 * give it's phandle to the ethernet node */