#1852 - add missing mags to LMG_Minigunn weapon

Added Missing:
"1000rnd_65x39_belt_green"
"1000rnd_65x39_belt_yellow"
"2000rnd_65x39_belt_green"
"2000rnd_65x39_belt_tracer_green_splash"
"2000rnd_65x39_belt_tracer_yellow_splash"
"2000rnd_65x39_belt_yellow"