Add dma support for lpuart. This function depend on DMA driver.
You can turn on it by write both the dmas and dma-name properties in dts node.
Signed-off-by: NYuan Yao <yao.yuan@freescale.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>