Semihosting: Fix file mode to load binaries on Windows

Trusted firmware binaries loaded via semihosting used to be
opened using 'r' mode (i.e. read mode).  This is fine on POSIX
conforming systems (including Linux) but for Windows it also means
that the file should be opened in text mode. 'rb' mode must be
specified instead for binary mode.  On POSIX conforming systems,
'rb' mode is equivalent to 'r' mode so it does no harm.

Fixes ARM-software/tf-issues#69

Change-Id: Ifa53f2ecfd765f572dea5dd73191f9fe2b2c2011

plat/fvp/plat_io_storage.c

@@ -60,22 +60,22 @@ static io_block_spec fip_block_spec = {
 
 static io_file_spec bl2_file_spec = {
 	.path = BL2_IMAGE_NAME,
-	.mode = FOPEN_MODE_R
+	.mode = FOPEN_MODE_RB
 };
 
 static io_file_spec bl31_file_spec = {
 	.path = BL31_IMAGE_NAME,
-	.mode = FOPEN_MODE_R
+	.mode = FOPEN_MODE_RB
 };
 
 static io_file_spec bl32_file_spec = {
 	.path = BL32_IMAGE_NAME,
-	.mode = FOPEN_MODE_R
+	.mode = FOPEN_MODE_RB
 };
 
 static io_file_spec bl33_file_spec = {
 	.path = BL33_IMAGE_NAME,
-	.mode = FOPEN_MODE_R
+	.mode = FOPEN_MODE_RB
 };
 
 static int open_fip(void *spec);