[pushed] microblaze-tdep: Add ATTRIBUTE_PRINTF to microblaze_debug

[Simon Marchi <simon.marchi@ericsson.com>]

I am getting this warning with clang:

/home/emaisin/src/binutils-gdb/gdb/microblaze-tdep.c:94:28: error: format string is not a string literal [-Werror,-Wformat-nonliteral]
       vprintf_unfiltered (fmt, args);
                           ^~~

Adding ATTRIBUTE_PRINTF to microblaze_debug gets rid of it.  Strangely,
gcc doesn't warn about non-literal format strings when calling vprintf
(or a vprintf-style function, like vprintf_unfiltered).  I filed this
gcc bug:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82206

gdb/ChangeLog:

	* microblaze-tdep.c (microblaze_debug): Add ATTRIBUTE_PRINTF.
---
 gdb/ChangeLog         | 4 ++++
 gdb/microblaze-tdep.c | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index adafa4c..88e7a6e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-09-21  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* microblaze-tdep.c (microblaze_debug): Add ATTRIBUTE_PRINTF.
+
 2017-09-21  Yao Qi  <yao.qi@linaro.org>
 
 	* configure.tgt (aarch64*-*-freebsd*): Add fbsd-tdep.o solib-svr4.o
diff --git a/gdb/microblaze-tdep.c b/gdb/microblaze-tdep.c
index 7547581..caa7d2f 100644
--- a/gdb/microblaze-tdep.c
+++ b/gdb/microblaze-tdep.c
@@ -82,7 +82,7 @@ static const char *microblaze_register_names[] =
 \f
 static unsigned int microblaze_debug_flag = 0;
 
-static void
+static void ATTRIBUTE_PRINTF (1, 2)
 microblaze_debug (const char *fmt, ...)
 { 
   if (microblaze_debug_flag)
-- 
2.7.4