Auto merge of #2710 - kraj:rv32, r=Amanieu
Auto merge of #2710 - kraj:rv32, r=Amanieu

riscv32: Define O_LARGEFILE

Some applications (e.g. nix) use this define and expect it to come from libc

Signed-off-by: Khem Raj <729d64b6f67515e258459a5f6d20ec88b2caf8df@gmail.com>

rust-lang/libc,rust-lang/libc,rust-lang/libc