radix-tree tests: properly initialize mutex

The pthread_mutex_t in regression1.c wasn't being initialized properly.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ross Zwisler <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Andrey Ryabinin <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

tools/testing/radix-tree/regression1.c

@@ -43,7 +43,7 @@
 #include "regression.h"
 
 static RADIX_TREE(mt_tree, GFP_KERNEL);
-static pthread_mutex_t mt_lock;
+static pthread_mutex_t mt_lock = PTHREAD_MUTEX_INITIALIZER;
 
 struct page {
 	pthread_mutex_t lock;