dmaengine: imx-sdma: add uart rom script

For the compatibility of NXP internal legacy kernel before 4.19 which
is based on uart ram script and upstreaming kernel based on uart rom
script, add both uart ram/rom script in latest sdma firmware. By default
uart rom script used.
Besides, add two multi-fifo scripts for SAI/PDM on i.mx8m/8mm and add
back qspi script miss for v4(i.mx7d/8m/8mm family, but v3 is for i.mx6).

rom script:
        uart_2_mcu_addr
	uartsh_2_mcu_addr /* through spba bus */
am script:
	uart_2_mcu_ram_addr
	uartsh_2_mcu_ram_addr /* through spba bus */

Please get latest sdma firmware from the below and put them into the path
(/lib/firmware/imx/sdma/):
https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git


/tree/imx/sdma

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Acked-by: Vinod Koul <vkoul@kernel.org>