tracing/probes: Move 'symbol' fetch method to kprobes

Move existing functions to trace_kprobe.c and add NULL entries to the
uprobes fetch type table.  I don't make them static since some generic
routines like update/free_XXX_fetch_param() require pointers to the
functions.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 5395d37..24ef6a3 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -115,6 +115,14 @@
 #define fetch_stack_string_size	NULL
 
 
+/* uprobes do not support symbol fetch methods */
+#define fetch_symbol_u8			NULL
+#define fetch_symbol_u16		NULL
+#define fetch_symbol_u32		NULL
+#define fetch_symbol_u64		NULL
+#define fetch_symbol_string		NULL
+#define fetch_symbol_string_size	NULL
+
 /* Fetch type information table */
 const struct fetch_type uprobes_fetch_type_table[] = {
 	/* Special types */