Removed BUILTIN_CHANNELS

Building client channels out of tree does not work reliable as the
dependencies can not be easily split. (exceptions may be simple ones
as echo channel)
It does complicate the build system and code though, so remove this
for maintainability reasons.

packaging/deb/freerdp-nightly/rules

@@ -10,7 +10,6 @@ DEB_CMAKE_EXTRA_FLAGS :=  -DCMAKE_SKIP_RPATH=FALSE \
                           -DCMAKE_SKIP_INSTALL_RPATH=FALSE \
                           -DWITH_PULSE=ON \
                           -DWITH_CHANNELS=ON \
-                          -DBUILTIN_CHANNELS=ON \
                           -DWITH_CUPS=ON \
                           -DWITH_PCSC=ON \
                           -DWITH_GSTREAMER_0_10=ON \

packaging/rpm/freerdp-nightly.spec

@@ -116,7 +116,6 @@ cp %{_topdir}/SOURCES/source_version freerdp-nightly-%{version}/.source_version
         -DCMAKE_SKIP_INSTALL_RPATH=FALSE \
         -DWITH_PULSE=ON \
         -DWITH_CHANNELS=ON \
-        -DBUILTIN_CHANNELS=ON \
         -DWITH_CUPS=ON \
         -DWITH_PCSC=ON \
         -DWITH_JPEG=ON \