Apply Patch "locktorture: Fix potential memory leak with rw lock test" to 3.15+ stable release

["石洋" <yang.s@xxxxxxxxxxxxxxx>]

Hi Greg,

The patch "locktorture: Fix potential memory leak with rw lock test" 
(commit f4dbba591945dc301c302672adefba9e2ec08dc5) fixed a kernel memory 
leak in locktorture, which came from me originally. It was just merged 
into 4.11 of Linus's tree, however, the patch is applicable to 3.15 till 
4.10 since the stable mailing list was omitted in the original review.

Could you please apply the patch to 3.15+ stable release? 3.15/.16/.17 
just have writer statistics, reader statistics was added since 3.18.

BTW, my linaro email account in the SOB is not valid anymore, please cc 
yang.s@xxxxxxxxxxxxxxx if needed.

Thanks,
Yang