USB: serial: sierra driver adding reset_resume function

This patch adds a new function to the sierra.c driver, sierra_reset_resume().
This new function completes the suite of Dynamic Power Management commands
in the sierra.c driver.

Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/serial/sierra.c |   30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)