unicore32: remove unused pmode argument in c_backtrace()

The pmode parameter isn't used in assembly - remove it.  Second argument
will be reused for printk() log level.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Link: http://lkml.kernel.org/r/20200418201944.482088-38-dima@arista.com


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>