arch/x86/acpigen: Allow writing buffers larger than 256 bytes

Currently only 256 bytes can be written at a time using the
acpigen_write_return_byte_buffer or acpigen_write_byte_buffer API's
and there can be cases where the buffer size can exceed this, hence
increase the number of bytes that can be written.

Change-Id: Ifaf508ae1d5c0eb2629ca112224bfeae1c644e58
Signed-off-by: Rizwan Qureshi <rizwan.qureshi@intel.com>
Signed-off-by: Sowmya V <v.sowmya@intel.com>
Reviewed-on: https://review.coreboot.org/18966
Tested-by: build bot (Jenkins)
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2 files changed