ARM: dts: msm: Fix bluetooth enable failure for SDXPRAIRIE

GPIO_17 of SDX55 LE MTP services as BT_I2S_0_SDO and bootstrap
pin EDL_MODE for QCA6391, QCA6391 have default pull-up for EDL_MODE
EDL_MODE should be sampled as logic high when enable bluetooth, but
the bias-pull-down config for GPIO19 will pull down EDL_MODE to logic
low for many HST01 boards, so cause bluetooth enable failure.

fix by correcting GPIO_19  pull mode from bias-pull-down
to bias-disable.

CRs-Fixed: 2485700
Change-Id: Ia903850f09a43b572fefe1af3e1613ac58a92c0a
Signed-off-by: Zijun Hu <zijuhu@codeaurora.org>