[BSP]更新NUVOTON M487 Sconscript

bsp/nuvoton_m487/applications/SConscript

-Import('RTT_ROOT')
-Import('rtconfig')
+# RT-Thread building script for component
+
 from building import *
 
-cwd     = os.path.join(str(Dir('#')), 'applications')
-src	= Glob('*.c')
+cwd = GetCurrentDir()
+src = Glob('*.c') + Glob('*.cpp')
 CPPPATH = [cwd, str(Dir('#'))]
 
 group = DefineGroup('Applications', src, depend = [''], CPPPATH = CPPPATH)