Fix WMS provide build failure

Heavily multithreaded QGIS build fails due to missing dependency between WMS
code and the Qt form code. This patch makes the dependency explicit.

Signed-off: Libor Pechacek <lpechacek@gmx.com>
---
 src/providers/wms/CMakeLists.txt |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/src/providers/wms/CMakeLists.txt
+++ b/src/providers/wms/CMakeLists.txt
@@ -12,6 +12,9 @@ SET (WMS_MOC_HDRS
 )
 
 IF (WITH_GUI)
+  SET(WMS_GUI_UIS
+    ../../ui/qgswmssourceselectbase.ui
+  )
   SET(WMS_GUI_SRCS
     qgswmsprovidergui.cpp
     qgswmssourceselect.cpp
@@ -29,6 +32,7 @@ IF (WITH_GUI)
   )
 ENDIF ()
 
+QT5_WRAP_UI (WMS_GUI_UIS_H  ${WMS_GUI_UIS})
 QT5_WRAP_CPP (WMS_MOC_SRCS ${WMS_MOC_HDRS})
 QT5_WRAP_CPP (WMS_GUI_MOC_SRCS ${WMS_GUI_MOC_HDRS})
 
@@ -57,7 +61,7 @@ INCLUDE_DIRECTORIES(SYSTEM
 )
 
 # static library
-ADD_LIBRARY(wmsprovider_a STATIC ${WMS_SRCS} ${WMS_MOC_SRCS})
+ADD_LIBRARY(wmsprovider_a STATIC ${WMS_GUI_UIS_H} ${WMS_SRCS} ${WMS_MOC_SRCS})
 TARGET_LINK_LIBRARIES(wmsprovider_a
   ${Qt5Xml_LIBRARIES}
   ${Qt5Core_LIBRARIES}