* Changed the way of accessing L3 target
  registers from standard base rather
  than relative to STDERRLOG_MAIN.

* Use ffs() to find error source from
  the L3_FLAGMUX_REGERRn register.

* Remove extra l3_base[] entry.

* Modified L3 custom error message.
Signed-off-by: NTodd Poynor <toddpoynor@google.com>
Signed-off-by: Nsricharan <r.sricharan@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>