In the wake of Recording Academy chief Neil Portnow’s ill-worded comments after the Grammy Awards Sunday night — in which he said female artists and executives need to “step up” — and a low number of nominees and winners who are women, a group of female music-industry senior executives have issued a letter calling for his resignation. The group, which is led by veteran music-business attorney Rosemary Carroll, also includes agents Cara Lewis, Natalia Nastaskin and Marsha Vlasic; John Legend manager Ty Stiklorius; Pharrell Williams manager Caron Veazey; Warner/Chappell publishing VP Katie Vinten; branding executive Marcie Allen and several others....