Remove NDK patch no longer necessary

ndk-patches/utmp.h.patch

@@ -1,17 +0,0 @@
-diff -u -r /home/fornwall/lib/android-ndk/sysroot/usr/include/utmp.h ./usr/include/utmp.h
---- /home/fornwall/lib/android-ndk/sysroot/usr/include/utmp.h	2017-11-09 09:57:12.000000000 +0100
-+++ ./usr/include/utmp.h	2017-11-15 12:01:37.108811692 +0100
-@@ -101,11 +101,8 @@
- struct utmp* getutent(void);
- void endutent(void);
- 
--
--#if __ANDROID_API__ >= 23
--int login_tty(int __fd) __INTRODUCED_IN(23);
--#endif /* __ANDROID_API__ >= 23 */
--
-+/* In Termux login_tty() is implemented in the libutil package to support android-21. */
-+int login_tty(int __fd);
- 
- __END_DECLS
-