ifdtool: Use perror for file write errors

The "Error while writing." error messages did not output a new line
which made the output look weird. With this patch, it should look like

$ ifdtool -x 3rdparty/mainboard/google/parrot/descriptor.bin
File 3rdparty/mainboard/google/parrot/descriptor.bin is 4096 bytes
Found Flash Descriptor signature at 0x00000010
Flash Region 0 (Flash Descriptor): 00000000 - 00000fff
Flash Region 1 (BIOS): 00200000 - 007fffff
Error while writing: Bad address
Flash Region 2 (Intel ME): 00001000 - 001fffff
Error while writing: Bad address
Flash Region 3 (GbE): 00fff000 - 00000fff (unused)
Flash Region 4 (Platform Data): 00fff000 - 00000fff (unused)

Change-Id: I784ff72d0673f167dbf0bd10921406abd685ce72
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/1299
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Tested-by: build bot (Jenkins)
1 file changed