SConscript: fix the `--keep` parameter for Keil

The old `--keep` parameter for Keil is wrong. RTFM of Keil and get it
right.

components/finsh/SConscript

@@ -28,10 +28,10 @@ msh.c
 
 CPPPATH = [cwd]
 if rtconfig.CROSS_TOOL == 'keil':
-    LINKFLAGS = ' --keep __fsym_*'
+    LINKFLAGS = ' --keep *.o(FSymTab)'
 
     if not GetDepend('FINSH_USING_MSH_ONLY'):
-        LINKFLAGS = LINKFLAGS + ' --keep __vsym_* '
+        LINKFLAGS = LINKFLAGS + ' --keep *.o(VSymTab) '
 else:
     LINKFLAGS = '' 
 

src/SConscript

@@ -9,9 +9,9 @@ if rtconfig.CROSS_TOOL == 'keil':
     # add more link flags for module and components_init.
     LINKFLAGS = ''
     if GetDepend('RT_USING_MODULE'):
-        LINKFLAGS = ' --keep __rtmsym_* '
+        LINKFLAGS = ' --keep *.o(RTMSymTab) '
     if GetDepend('RT_USING_COMPONENTS_INIT'):
-        LINKFLAGS = ' --keep __rt_init* '
+        LINKFLAGS = ' --keep *.o(.rti_fn.*) '
 else:
     LINKFLAGS = ''