Provide getdelim and getline compat shims

These are portable implementations from NetBSD that are needed on
Windows and perhaps some other platforms with the new versions of
the mlkem tests.

include/compat/stdio.h

@@ -18,6 +18,18 @@
 #include_next <stdio.h>
 #endif
 
+#ifndef HAVE_GETDELIM
+#include <sys/types.h>
+#define getdelim libressl_getdelim
+ssize_t getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp);
+#endif
+
+#ifndef HAVE_GETLINE
+#include <sys/types.h>
+#define getline libressl_getline
+ssize_t getline(char **buf, size_t *bufsiz, FILE *fp);
+#endif
+
 #ifndef HAVE_ASPRINTF
 #include <stdarg.h>
 #define vasprintf libressl_vasprintf