Staging: ste_rmi4: add new line after declarations

This patch fixes checkpatch.pl warning in synaptics_i2c_rmi4.c file
WARNING : Missing a blank line after declarations

Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>