fpga: Simplify error path in fpga_add

Check !desc earlier to simplify code.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Reviewed-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>

drivers/fpga/fpga.c

@@ -148,10 +148,14 @@ int fpga_add(fpga_type devtype, void *desc)
 {
 	int devnum = FPGA_INVALID_DEVICE;
 
+	if (!desc) {
+		printf("%s: NULL device descriptor\n", __func__);
+		return devnum;
+	}
+
 	if (next_desc < 0) {
 		printf("%s: FPGA support not initialized!\n", __func__);
 	} else if ((devtype > fpga_min_type) && (devtype < fpga_undefined)) {
-		if (desc) {
 		if (next_desc < CONFIG_MAX_FPGA_DEVICES) {
 			devnum = next_desc;
 			desc_table[next_desc].devtype = devtype;
@@ -161,9 +165,6 @@ int fpga_add(fpga_type devtype, void *desc)
 			       __func__);
 		}
 	} else {
-			printf("%s: NULL device descriptor\n", __func__);
-		}
-	} else {
 		printf("%s: Unsupported FPGA type %d\n", __func__, devtype);
 	}