install-alpine: include clang headers

Steven Noonan · Steven Noonan · commit a2c07d8a446e · 2020-01-21T01:44:08.000-08:00
Needed for emmintrin.h with reference ed25519/curve25519 implementation.

Signed-off-by: Steven Noonan &lt;steven@valvesoftware.com&gt;
diff --git a/.travis/install-alpine.sh b/.travis/install-alpine.sh
@@ -9,6 +9,7 @@ apk update
 # Base build packages
 PACKAGES=(
 	clang
+	clang-dev
 	gcc
 	g++
 	cmake
