AT91Bootstrap version 4 is available only for SAM9X60, SAMA5D2, SAMA5D3,
SAMA5D4, SAMA7G5. Thus use v4.0.1 for the above targets and v3.10.4 for
the rest of them. With the switch to v4 AT91Bootstrap binaries are now
on build/binaries. Take also this into account. Also, patches directory
is not needed anymore with the version update.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>