core, wimax: Fix clang-tidy readability-implicit-bool-conversion warnings

Fix the following two cases of clang-tidy readability-implicit-bool-conversion warnings, where a bool is being passed to a function that expects to receive an int.

• The constructor int64x64_t(int64_t, uint64_t).
• The function GrantManagementSubheader::SetPm(uint8_t).