utest: UTEST_TMPFS_CP -> RT_UTEST_TMPFS_CP

Signed-off-by: Chen Wang <unicorn_wang@outlook.com>

examples/utest/testcases/tmpfs/Kconfig

@@ -1,6 +1,6 @@
 menu "Tmpfs Testcase"
 
-config UTEST_TMPFS_CP
+config RT_UTEST_TMPFS_CP
     bool "tmpfs cp test"
     default n
 endmenu

examples/utest/testcases/tmpfs/SConscript

@@ -5,7 +5,7 @@ cwd     = GetCurrentDir()
 src     = []
 CPPPATH = [cwd]
 
-if GetDepend(['RT_USING_SMART','UTEST_TMPFS_CP']):
+if GetDepend(['RT_USING_SMART','RT_UTEST_TMPFS_CP']):
     src += ['tmpfs.c']
 
 group = DefineGroup('utestcases', src, depend = ['RT_USING_UTESTCASES'], CPPPATH = CPPPATH)