add compat getopt implementation, remove patches

This adds a getopt implementation for compatibility where it is not
available, removing a couple of regress patches.

Note, this is a slightly modified copy from OpenBSD libc that doesn't
expose getopt_long, which has dependency conflicts with Windows system
headers and isn't needed anyway.

crypto/CMakeLists.txt

@@ -818,6 +818,11 @@ if(NOT HAVE_FREEZERO)
 	set(EXTRA_EXPORT ${EXTRA_EXPORT} freezero)
 endif()
 
+if(NOT HAVE_GETOPT)
+	set(CRYPTO_SRC ${CRYPTO_SRC} compat/getopt_long.c)
+	set(EXTRA_EXPORT ${EXTRA_EXPORT} getopt)
+endif()
+
 if(NOT HAVE_GETPAGESIZE)
 	set(CRYPTO_SRC ${CRYPTO_SRC} compat/getpagesize.c)
 endif()