- RISC-V 32 bits linux/glibc didn't provide gettimeofday anymore
after upstream, because RV32 didn't have backward compatible issue,
so RV32 only support 64 bits time related system call.
- So using clock_gettime64 call instead for rv32 libgloss.
- For prevent confuse about what BSD license variant we used, 2- or
3-clause license, we change the license to FreeBSD license to make
it unambiguously refers to the 2-clause license.