CMake: Add -fPIC also for OBJECT libraries

add_qtc_library would have set the POSITION_INDEPENDENT_CODE property
for STATIC libraries on UNIX based systems.

The OBJECT libraries need the same treatment.

Change-Id: Ia333a36ea0f35d7db3ed876cdde5b895b47644c7
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

cmake/QtCreatorAPI.cmake

@@ -188,7 +188,7 @@ function(add_qtc_library name)
     set(TEST_DEFINES WITH_TESTS SRCDIR="${CMAKE_CURRENT_SOURCE_DIR}")
   endif()
 
-  if(_arg_STATIC AND UNIX)
+  if((_arg_STATIC OR _arg_OBJECT) AND UNIX)
     # not added by Qt if reduce_relocations is turned off for it
     set_target_properties(${name} PROPERTIES POSITION_INDEPENDENT_CODE ON)
   endif()

src/libs/3rdparty/cplusplus/CMakeLists.txt

@@ -41,7 +41,6 @@ add_qtc_library(3rd_cplusplus OBJECT
     TypeVisitor.cpp TypeVisitor.h
     cppassert.h
   SKIP_PCH
-  PROPERTIES POSITION_INDEPENDENT_CODE ON
 )
 
 set(export_symbol_declaration DEFINES CPLUSPLUS_BUILD_LIB)

src/libs/sqlite/CMakeLists.txt

@@ -1,5 +1,5 @@
 add_qtc_library(SqliteC OBJECT
-    PROPERTIES AUTOMOC OFF AUTOUIC OFF QT_COMPILE_OPTIONS_DISABLE_WARNINGS ON POSITION_INDEPENDENT_CODE ON
+    PROPERTIES AUTOMOC OFF AUTOUIC OFF QT_COMPILE_OPTIONS_DISABLE_WARNINGS ON
     DEFINES SQLITE_CORE SQLITE_CUSTOM_INCLUDE=config.h $<$<CONFIG:Debug>:SQLITE_DEBUG>
     PROPERTIES COMPILE_OPTIONS $<IF:$<CXX_COMPILER_ID:MSVC>,/FIconfig.h,-includeconfig.h>
     PUBLIC_INCLUDES