bus/fslmc: fix parse method for bus devices

bus/fslmc: fix parse method for bus devices

Current code expects that bus->parse() would get a string containing
the name of the bus. That is incorrect. bus->parse() is expected
to have strings like:
  dpni.1,key=val
  dpio.2,key=val

when user passed:
  -b fslmc:dpni.1,key=val

This commit fixes this behavior.

Fixes: 50245be05d1a ("bus/fslmc: support device blacklisting")
Cc: stable@dpdk.org
Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>