meta-phosphor: libvncserver: pin PACKAGECONFIG

PACKAGECONFIGs are added upstream frequently.  Avoid new implicit
dependencies by pinning to the exact options required by OpenBMC today.

(From meta-phosphor rev: a604537070251e0a391b3eccf3a0c6b9d528a5ae)

Change-Id: Id89749f408512118ce2a29a71f3f033fd79a3221
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-phosphor/recipes-graphics/libvncserver/libvncserver_%.bbappend b/meta-phosphor/recipes-graphics/libvncserver/libvncserver_%.bbappend
index 849255a..fa15047 100644
--- a/meta-phosphor/recipes-graphics/libvncserver/libvncserver_%.bbappend
+++ b/meta-phosphor/recipes-graphics/libvncserver/libvncserver_%.bbappend
@@ -1,2 +1 @@
-PACKAGECONFIG_append = " openssl"
-PACKAGECONFIG_remove = "gcrypt gnutls png sdl"
+PACKAGECONFIG = "jpeg lzo systemd zlib openssl"