Enable -fPIC to fix linking static libraries when building with Qt6

Otherwise the build would fail:
/usr/lib64/gcc/x86_64-suse-linux/11/../../../../x86_64-suse-linux/bin/ld: ../lib/libkonsoleprivate_core.a(ShellCommand.cpp.o): warning: relocation against `_ZN7QString6_emptyE@@Qt_6' in read-only section `.text'
/usr/lib64/gcc/x86_64-suse-linux/11/../../../../x86_64-suse-linux/bin/ld: ../lib/libkonsoleprivate_core.a(ShellCommand.cpp.o): relocation R_X86_64_PC32 against symbol `_ZN10QByteArray6_emptyE@@Qt_6' can not be used when making a shared object; recompile with -fPIC
/usr/lib64/gcc/x86_64-suse-linux/11/../../../../x86_64-suse-linux/bin/ld: final link failed: bad value

This seems to affect both STATIC and OBJECT CMake library types.

src/CMakeLists.txt

@@ -89,6 +89,8 @@ ecm_qt_declare_logging_category(
 )
 
 add_library(konsoleprivate_core STATIC ${konsoleprivate_core_SRCS})
+# Needed to link this static lib to shared libs
+set_target_properties(konsoleprivate_core PROPERTIES POSITION_INDEPENDENT_CODE ON)
 target_link_libraries(konsoleprivate_core ${konsole_LIBS})
 
 set(konsolehelpers_SRCS
@@ -98,6 +100,7 @@ add_library(konsolehelpers
     STATIC
     ${konsolehelpers_SRCS}
 )
+set_target_properties(konsolehelpers PROPERTIES POSITION_INDEPENDENT_CODE ON)
 target_link_libraries(konsolehelpers
     Qt::Core
     Qt::Widgets

src/colorscheme/CMakeLists.txt

@@ -26,6 +26,9 @@ add_library(konsolecolorscheme
     STATIC
     ${konsole_colorscheme_SRCS}
 )
+# Needed to link this static lib to shared libs
+set_target_properties(konsolecolorscheme PROPERTIES POSITION_INDEPENDENT_CODE ON)
+
 generate_export_header(konsolecolorscheme BASE_NAME konsolecolorscheme)
 target_include_directories(konsolecolorscheme
     PUBLIC ${CMAKE_CURRENT_BINARY_DIR}

src/decoders/CMakeLists.txt

@@ -4,6 +4,8 @@ add_library(konsoledecoders
     PlainTextDecoder.cpp
     HTMLDecoder.cpp
 )
+
+set_target_properties(konsoledecoders PROPERTIES POSITION_INDEPENDENT_CODE ON)
 generate_export_header(konsoledecoders BASE_NAME konsoledecoders)
 target_include_directories(konsoledecoders
     PUBLIC ${CMAKE_CURRENT_BINARY_DIR}

src/keyboardtranslator/CMakeLists.txt

@@ -6,6 +6,8 @@ add_library(keyboardtranslator
     KeyboardTranslator.cpp
     KeyboardTranslatorReader.cpp
 )
+# Needed to link this static lib to shared libs
+set_target_properties(keyboardtranslator PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
 target_link_libraries(
     keyboardtranslator

src/profile/CMakeLists.txt

@@ -12,6 +12,8 @@ OBJECT
     ProfileModel.cpp
     ${konsoleprofile_SRCS}
 )
+set_property(TARGET konsoleprofile PROPERTY POSITION_INDEPENDENT_CODE ON)
+
 generate_export_header(konsoleprofile BASE_NAME konsoleprofile)
 target_include_directories(konsoleprofile PUBLIC ${CMAKE_CURRENT_BINARY_DIR})
 target_link_libraries(

src/session/CMakeLists.txt

@@ -30,6 +30,9 @@ add_library(konsolesession
     OBJECT
     ${konsole_session_SRCS}
 )
+
+set_property(TARGET konsolesession PROPERTY POSITION_INDEPENDENT_CODE ON)
+
 generate_export_header(konsolesession BASE_NAME konsolesession)
 target_include_directories(konsolesession PUBLIC ${CMAKE_CURRENT_BINARY_DIR})
 target_link_libraries(