usb_bam: Get rid of usb_bam_set_qdss_core and usb_bam_get_qdss_idx

usb_bam_set_qdss_core API is currently used by QDSS function driver
to notify usb_bam about the USB core to which QDSS function is bound.
usb_bam can however determine this information from the connections
info passed via devicetree. Remove this API and rather let usb_bam
figure this out while parsing the BAM connections.
While at it also make coresight driver not bother about connection
index as this is not relevant for coresight. And change function
drivers to directly pass usb_bam_type (DWC3 or CI/HSIC) when
querying connection indexes which will allow to have separate
usb_bam_connections array for each BAM and eventually we can have
usb_bam platform driver as multi instance and pass connections
information for different USB BAMs using separate DT nodes.

Change-Id: I2f794751b102ab7200756245bce546dda41a1f90
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>