[NFC] As part of using inclusive language within the llvm project, this patch replaces master with main in `SubModule2.h`. Reviewed By: sammccall Differential Revision: https://reviews.llvm.org/D114100
[NFC] As part of using inclusive language within the llvm project, this patch replaces master with main in `SubModule2.h`. Reviewed By: sammccall Differential Revision: https://reviews.llvm.org/D114100