fix(plat/st): remove double space

Replace double space with single space in stm32cubeprogrammer_usb.c.

Change-Id: I717b136119e85fe8e25dd540758525f995200458
Signed-off-by: Yann Gautier <yann.gautier@st.com>
diff --git a/plat/st/common/stm32cubeprogrammer_usb.c b/plat/st/common/stm32cubeprogrammer_usb.c
index 4cd210e..19a6bba 100644
--- a/plat/st/common/stm32cubeprogrammer_usb.c
+++ b/plat/st/common/stm32cubeprogrammer_usb.c
@@ -116,7 +116,7 @@
 	dfu->address += *len;
 
 	if (dfu->address - dfu->base > dfu->len) {
-		return  -EIO;
+		return -EIO;
 	}
 
 	return 0;