V4L/DVB (8658): lgs8gl5: fix build warnings

Fix the following build warnings:

lgs8gl5.c: In function 'lgs8gl5_read_reg':
lgs8gl5.c:95: warning: unused variable 'j'
lgs8gl5.c: In function 'lgs8gl5_update_alt_reg':
lgs8gl5.c:135: warning: unused variable 'j'
lgs8gl5.c: In function 'lgs8gl5_read_ber':
lgs8gl5.c:300: warning: unused variable 'state'
lgs8gl5.c: In function 'lgs8gl5_read_ucblocks':
lgs8gl5.c:332: warning: unused variable 'state'
lgs8gl5.c: At top level:
lgs8gl5.c:181: warning: 'lgs8gl5_set_inversion' defined but not used

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>