hv_balloon: disable warning when floor reached

It is not an error if the host requests to balloon down, but the VM
refuses to do so. Without this change a warning is logged in dmesg
every five minutes.

Fixes:  b3bb97b8 ("Drivers: hv: balloon: Add logging for dynamic memory operations")
Signed-off-by: NOlaf Hering <olaf@aepfle.de>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20201008071216.16554-1-olaf@aepfle.deSigned-off-by: NWei Liu <wei.liu@kernel.org>

drivers/hv/hv_balloon.c

@@ -1275,7 +1275,7 @@ static void balloon_up(struct work_struct *dummy)
 
 	/* Refuse to balloon below the floor. */
 	if (avail_pages < num_pages || avail_pages - num_pages < floor) {
-		pr_warn("Balloon request will be partially fulfilled. %s\n",
+		pr_info("Balloon request will be partially fulfilled. %s\n",
 			avail_pages < num_pages ? "Not enough memory." :
 			"Balloon floor reached.");