GUACAMOLE-1026: Use freerdp3 within Dockerfile.

Dockerfile

@@ -64,7 +64,7 @@ ARG PREFIX_DIR=/opt/guacamole
 # library (these can be overridden at build time if a specific version is
 # needed)
 #
-ARG WITH_FREERDP='2(\.\d+)+'
+ARG WITH_FREERDP='3(\.\d+)+'
 ARG WITH_LIBSSH2='libssh2-\d+(\.\d+)+'
 ARG WITH_LIBTELNET='\d+(\.\d+)+'
 ARG WITH_LIBVNCCLIENT='LibVNCServer-\d+(\.\d+)+'
@@ -90,6 +90,7 @@ ARG FREERDP_OPTS="\
     -DWITH_GSSAPI=OFF \
     -DWITH_IPP=OFF \
     -DWITH_JPEG=ON \
+    -DWITH_KRB5=ON \
     -DWITH_LIBSYSTEMD=OFF \
     -DWITH_MANPAGES=OFF \
     -DWITH_OPENH264=OFF \
@@ -145,7 +146,7 @@ RUN ${BUILD_DIR}/src/guacd-docker/bin/build-all.sh
 RUN ${BUILD_DIR}/src/guacd-docker/bin/list-dependencies.sh \
         ${PREFIX_DIR}/sbin/guacd               \
         ${PREFIX_DIR}/lib/libguac-client-*.so  \
-        ${PREFIX_DIR}/lib/freerdp2/*guac*.so   \
+        ${PREFIX_DIR}/lib/freerdp3/*guac*.so   \
         > ${PREFIX_DIR}/DEPENDENCIES
 
 # Use same Alpine version as the base for the runtime image
@@ -202,4 +203,3 @@ EXPOSE 4822
 # PREFIX_DIR build argument.
 #
 CMD /opt/guacamole/sbin/guacd -b 0.0.0.0 -L $GUACD_LOG_LEVEL -f
-