tools lib symbols: Introduce kallsyms__is_function()

Out of symbol_type__is_a(type, MAP__FUNCTION), which is the only variant
used so far, useful in a kallsyms library and one more step in ditching
the MAP__FUNCTION/VARIABLE split.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-faonqs76n5808z9mq77edr94@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/symbol/kallsyms.c

@@ -10,6 +10,12 @@ u8 kallsyms2elf_type(char type)
 	return (type == 't' || type == 'w') ? STT_FUNC : STT_OBJECT;
 }
 
+bool kallsyms__is_function(char symbol_type)
+{
+	symbol_type = toupper(symbol_type);
+	return symbol_type == 'T' || symbol_type == 'W';
+}
+
 int kallsyms__parse(const char *filename, void *arg,
 		    int (*process_symbol)(void *arg, const char *name,
 					  char type, u64 start))

tools/lib/symbol/kallsyms.h

@@ -20,6 +20,8 @@ static inline u8 kallsyms2elf_binding(char type)
 
 u8 kallsyms2elf_type(char type);
 
+bool kallsyms__is_function(char symbol_type);
+
 int kallsyms__parse(const char *filename, void *arg,
 		    int (*process_symbol)(void *arg, const char *name,
 					  char type, u64 start));