Fix an unused parameter warning
Fix an unused parameter warning

test_sg.c's main doesn't use its argv parameter, and so the compiler
warns us this is the case.  This patch stops it from warning us.

simonjwright/stlink,gtalusan/stlink,swegener/stlink,braincorp/stlink,fedorcomander/stlink,gtalusan/stlink,12019/stlink,swegener/stlink,fedorcomander/stlink,trigrass2/stlink,simonjwright/stlink,braincorp/stlink,ros2/stlink,chaosAD/stlink,12019/stlink,chaosAD/stlink,trigrass2/stlink,ros2/stlink