Checked out the head of -portable today to start trying to build it on
macOS, under the assumption that since Linux and FreeBSD are merged I
stand a chance of making progress without knowing what I'm doing. (So
far: kind of.)

Anyway, here's a typo.

diff --git a/configure.ac b/configure.ac
index febc60ec..ba66160d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -197,7 +197,7 @@ PKG_CHECK_MODULES(
 	LIBCRYPTO,
 	libcrypto,
 	[
-	 	AM_CFLAGS="$LIBCRYTPO_CFLAGS $AM_CFLAGS"
+		AM_CFLAGS="$LIBCRYPTO_CFLAGS $AM_CFLAGS"
 		CFLAGS="$AM_CFLAGS $SAVED_CFLAGS"
 		LIBS="$LIBCRYPTO_LIBS $LIBS"
 		found_libcrypto=yes