board: atmel: sama5d2_icp: add periph reset in SPL hw init

board: atmel: sama5d2_icp: add periph reset in SPL hw init

Some periphs on the board need to be reset by holding their reset GPIO down
for a specific time period.
On a warm reset, the periphs are not being reset by any reset pin and may be
in a wrong state.
Reset them in the SPL to make sure we are booting into the correct state
machine of the specific board periphs (KSZ eth switch, USB hub, HSIC eth,
Ethercat)

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>