HACK: use i64 for time_t on musl

Musl has use a 64-bit time_t since 1.2.0, but rust still uses the old
32-bit time_t on 32-bit platforms.
rust-lang/libc#2088 will eventually fix this,
but until then use i64 for time_t on musl in our tree.  This will
break binary compatibility with rust crates built against musl outside
our tree, but those shouldn't get mixed with our tree.

Bug: 216192129
Test: m USE_HOST_MUSL=true host-native -k
Change-Id: Iaafd06e180514157015607be50f625cb0661e1b8

patches/musl_time_t.patch

@@ -0,0 +1,13 @@
+diff --git a/src/unix/linux_like/linux/musl/mod.rs b/src/unix/linux_like/linux/musl/mod.rs
+index 70710734..929108ce 100644
+--- a/src/unix/linux_like/linux/musl/mod.rs
++++ b/src/unix/linux_like/linux/musl/mod.rs
+@@ -9,7 +9,7 @@ pub type clock_t = c_long;
+                 See #1848 for more info."
+     )
+ )]
+-pub type time_t = c_long;
++pub type time_t = i64;
+ pub type suseconds_t = c_long;
+ pub type ino_t = u64;
+ pub type off_t = i64;

src/unix/linux_like/linux/musl/mod.rs

@@ -9,7 +9,7 @@ pub type clock_t = c_long;
                 See #1848 for more info."
     )
 )]
-pub type time_t = c_long;
+pub type time_t = i64;
 pub type suseconds_t = c_long;
 pub type ino_t = u64;
 pub type off_t = i64;