Haiku: Native support

This is the rest of the changes to the native code of .NET from the
initial porting effort in 2023.

Author: trungnt2910

src/mono/mono/utils/mono-dl.c

@@ -50,6 +50,8 @@ fix_libc_name (const char *name)
 		return "/usr/lib/libc.dylib";
 #elif defined (__FreeBSD__)
 		return "libc.so.7";
+#elif defined (HOST_HAIKU)
+		return "libroot.so";
 #elif defined (LIBC_SO)
 		return LIBC_SO;
 #else