Revert "NOJIRA: Rename color switch cc to cpp for clang support (SiliconLabsSoftware#24)"

This reverts commit 8d284db.

Origin: SiliconLabsSoftware#146
Signed-off-by: Philippe Coval <philippe.coval@silabs.com>

Author: rzr

applications/zpc/components/zwave_command_classes/CMakeLists.txt

@@ -46,7 +46,7 @@ add_library(
   src/zwave_command_class_supervision.c
   src/zwave_command_class_supervision_process.cpp
   src/zwave_command_class_sound_switch.c
-  src/zwave_command_class_switch_color.cpp
+  src/zwave_command_class_switch_color.c
   src/zwave_command_class_switch_multilevel.c
   src/zwave_command_class_thermostat_mode.c
   src/zwave_command_class_thermostat_fan_mode.c