drm/amdgpu: Fix signedness bug in __amdgpu_eeprom_xfer()

The i2c_transfer() function returns negatives or else the number of
messages transferred.  This code does not work because ARRAY_SIZE()
is type size_t and so that means negative values of "r" are type
promoted to high positive values which are greater than the ARRAY_SIZE().

Fix this by changing the < to != which works regardless of type
promotion.

Fixes: 746b5847 ("drm/amdgpu: Fixes to the AMDGPU EEPROM driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c

@@ -147,7 +147,7 @@ static int __amdgpu_eeprom_xfer(struct i2c_adapter *i2c_adap, u32 eeprom_addr,
 		/* This constitutes a START-STOP transaction.
 		 */
 		r = i2c_transfer(i2c_adap, msgs, ARRAY_SIZE(msgs));
-		if (r < ARRAY_SIZE(msgs))
+		if (r != ARRAY_SIZE(msgs))
 			break;
 
 		if (!read) {