scripts/gdb: Perform path expansion to lx-symbol's arguments

Python doesn't do automatic expansion of paths.  In case one passes path
of the from ~/foo/bar the gdb scripts won't automatically expand that
and as a result the symbols files won't be loaded.

Fix this by explicitly expanding all paths which begin with "~"

Link: http://lkml.kernel.org/r/1467127337-11135-5-git-send-email-kieran@bingham.xyz
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb/linux/symbols.py

@@ -153,7 +153,7 @@ lx-symbols command."""
             saved_state['breakpoint'].enabled = saved_state['enabled']
 
     def invoke(self, arg, from_tty):
-        self.module_paths = arg.split()
+        self.module_paths = [os.path.expanduser(p) for p in arg.split()]
         self.module_paths.append(os.getcwd())
 
         # enforce update