Add sha256-prf.tls into libcrypto build

This was forgotten in commit ab637dcb37057f433932ecc8d45e129cd2d14170.

Signed-hostap: Jouni Malinen <j@w1.fi>

src/crypto/Makefile

@@ -41,6 +41,7 @@ LIB_OBJS= \
 	sha1-tlsprf.o \
 	sha1-tprf.o \
 	sha256.o \
+	sha256-prf.o \
 	sha256-tlsprf.o \
 	sha256-internal.o