efi_loader: correctly aligned transmit buffer

efi_loader: correctly aligned transmit buffer

Calling net_send_packet() requires that the buffer is aligned to a multiple
of PKTALIGN (= ARCH_DMA_MINALIGN). The UEFI spec does not require
efi_net_transmit() to be called with a buffer with any special alignment.
So we have to copy to an aligned buffer. The current coding copies to an
aligned buffer only if CONFIG_EFI_LOADER_BOUNCE_BUFFER=y. Many boards
like the Odroid C2 do not use a bounce buffer.

With the patch we copy to a correctly aligned buffer in all cases.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>