headers: fix missing mode_t

Signed-off-by: Dirk Neukirchen <dirkneukirchen@web.de>
Reviewed-by: Aris Adamantiadis <aris@0xbadc0de.be>

libssh/patches/002-musl_mode_t.patch

@@ -0,0 +1,10 @@
+--- a/include/libssh/libssh.h
++++ b/include/libssh/libssh.h
+@@ -58,6 +58,7 @@
+ #else /* _MSC_VER */
+   #include <unistd.h>
+   #include <inttypes.h>
++  #include <sys/types.h>
+ #endif /* _MSC_VER */
+ 
+ #ifdef _WIN32