Fix getgrgid_r to accept gid_t.

[crlf0710]

Closes #1320.

[rust-highfive]

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[gnzlbg]

What are the types of gid_t and uid_t on each of the modified architectures?

[crlf0710]

L:\ThirdParty\rust\libc>rg type | rg gid_t
src\wasi.rs:pub type gid_t = u32;
src\fuchsia\mod.rs:pub type gid_t = u32;
src\redox\mod.rs:pub type gid_t = c_int;
src\unix\mod.rs:pub type gid_t = u32;

L:\ThirdParty\rust\libc>rg type | rg uid_t
src\wasi.rs:pub type uid_t = u32;
src\fuchsia\mod.rs:pub type uid_t = u32;
src\redox\mod.rs:pub type uid_t = c_int;
src\unix\mod.rs:pub type uid_t = u32;
src\unix\bsd\freebsdlike\dragonfly\mod.rs:pub type uuid_t = ::uuid;

Consistent!

[gnzlbg]

So this doesn't change any type, only the type alias used right?

[crlf0710]

Yes, i think so.

[gnzlbg]

@bors: r+

[bors]

📌 Commit 1cf0294 has been approved by gnzlbg

[bors]

⌛ Testing commit 1cf0294 with merge e2bf06c...

[bors]

☀️ Test successful - checks-cirrus, checks-travis, status-appveyor
Approved by: gnzlbg
Pushing e2bf06c to master...