d/rules: Build tweaked version of ls1028ardb platform for audio lineout
Build a version of the firmware with a tweaked RCW to enable I2S signals on EC1_TXD2 (SAI4_TX_DATA) and EC1_GTX_CLK (SAI4_TX_SYNC) pins.
Signed-off-by: Martyn Welch martyn.welch@collabora.com