firmware: qcom_scm: Add API to get waitqueue IRQ info

firmware: qcom_scm: Add API to get waitqueue IRQ info

Bootloader and firmware for SM8650 and older chipsets expect node
name as "qcom_scm", in order to patch the wait queue IRQ information.
However, DeviceTree uses node name "scm" and this mismatch prevents
firmware from correctly identifying waitqueue IRQ information. Waitqueue
IRQ is used for signaling between secure and non-secure worlds.

To resolve this, introduce qcom_scm_get_waitq_irq() that'll get the
hardware IRQ number to be used from firmware instead of relying on data
provided by devicetree, thereby bypassing the DeviceTree node name
mismatch.

This hardware IRQ number is converted to a Linux IRQ number using newly
qcom_scm_fill_irq_fwspec_params(). This Linux IRQ number is then
supplied to the threaded_irq call.

Reviewed-by: Bartosz Golaszewski <brgl@kernel.org>
Signed-off-by: Unnathi Chalicheemala <unnathi.chalicheemala@oss.qualcomm.com>
Signed-off-by: Shivendra Pratap <shivendra.pratap@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20251217-multi_waitq_scm-v11-1-f21e50e792b8@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>