If execution jumps to the err_kfree label, error_bl is evaluated
before it is initialized. Fix this by initializing it to zero.

Fixes: 2539da66 ("Input: iqs5xx - preserve bootloader errors")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/1611592500-32209-1-git-send-email-jeff@labundy.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>