CID-300588, 307566, 307559

[hlaccabu]

Fixing a few Coverity issues found in a couple files in /src/runtime_src/core/pcie/driver/linux/xocl/userpf

Problem solved by the commit

A few issues found by the Coverity scan that could cause problems.

Bug / issue (if any) fixed, which PR introduced the bug, how it was discovered

Copy into fixed size buffer, uninitialized scalar variable, and logically dead code in xocl_hwctx.c, xocl_ioctl.c, and xocl_sysfs.c, respectively.

How problem was solved, alternative solutions (if any) and why they were rejected

Use strlcpy() instead of strcpy(), initialized uninit variable to 0 (as is consistent with rest of code), and removed conditional that was logically dead.