sparc: remove unused variable strtab

sparc: remove unused variable strtab

The commit 1b35a57b1c178 ("sparc32: Kill off software 32-bit multiply/divide
 routines") removed the last usage of strtab in funtion module_frob_arch_sections
Therefore, it can be removed now.

Reported-by: kernel test robot <lkp@intel.com>
Cc: sparclinux@vger.kernel.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Alex Shi <alexs@kernel.org>
Reviewed-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>