Added O_PATH, O_EXEC, O_SEARCH to musl.

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

@@ -124,6 +124,9 @@ pub const EFD_CLOEXEC: ::c_int = 0x80000;
 pub const BUFSIZ: ::c_uint = 1024;
 pub const TMP_MAX: ::c_uint = 10000;
 pub const FOPEN_MAX: ::c_uint = 1000;
+pub const O_PATH: ::c_int = 0o10000000;
+pub const O_EXEC: ::c_int = 0o10000000;
+pub const O_SEARCH: ::c_int = 0o10000000;
 pub const O_ACCMODE: ::c_int = 0o10000003;
 pub const O_NDELAY: ::c_int = O_NONBLOCK;
 pub const NI_MAXHOST: ::socklen_t = 255;