Fix fail to detect keyboard backlight when initial value is zero

[Alex Murray]

See attached patch - basically if the kbd backlight is zero at startup
upower will currently fail to detect it since it sees a value of 0 as
an error - instead don't bother to check for error since
g_ascii_strtoll returns 0 as both error and a valid conversion of 0.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Keyboard-backlight-of-zero-is-not-an-error.patch
Type: text/x-patch
Size: 911 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/devkit-devel/attachments/20101018/d03a3904/attachment.bin>