configs/raspberrypi: use EABIhf

The SoC of the Raspberry Pi 1 is an ARM1176JZF-S, which features a VFPv2
FPU, so use the EABIhf target ABI, which is more efficient than EABI.
This is also the default on Raspbian.

Signed-off-by: Benoît Thébaudeau <benoit@wsystem.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>