Fix RGF_MISSILES not giving to missiles unless they had NOBLOCKMAP removed. (Alt version)

A_RadiusGive's RGF_MISSILES flag doesn't give to most projectiles. You had to remove NOBLOCKMAP for it to work, which can cause really bizarre behaviour with projectiles, and 99% of projectiles have that flag implicit. This fix makes it more like newer ZDoom revisions.

This is an alternate, two-line version to !55 (closed)