drivers: soc: sdx_ext_ipc: Fix devm_request_threaded_irq call

Run sdx_ext_ipc_wakeup_irq in isr context and not in thread
context.

Change-Id: Ida0c6653c20ea20077881b30552f68929fdf1241
Signed-off-by: Shreyas K K <shrekk@codeaurora.org>