mmc: use the generic error number

Use the generic error number instead of specific error number.
If use the generic error number, it can debug more easier.

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index d584b0b..1d6d2fd 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -170,7 +170,7 @@
 				       cmd_timeout);
 			} else {
 				puts("timeout.\n");
-				return COMM_ERR;
+				return -ECOMM;
 			}
 		}
 		time++;
@@ -260,7 +260,7 @@
 			} else {
 				printf("%s: Timeout for status update!\n",
 				       __func__);
-				return TIMEOUT;
+				return -ETIMEDOUT;
 			}
 		}
 	} while ((stat & mask) != mask);
@@ -289,9 +289,9 @@
 	sdhci_reset(host, SDHCI_RESET_CMD);
 	sdhci_reset(host, SDHCI_RESET_DATA);
 	if (stat & SDHCI_INT_TIMEOUT)
-		return TIMEOUT;
+		return -ETIMEDOUT;
 	else
-		return COMM_ERR;
+		return -ECOMM;
 }
 
 static int sdhci_set_clock(struct mmc *mmc, unsigned int clock)