core: Refactor wcore_tinfo_get()
core: Refactor wcore_tinfo_get()

Move declaration of `struct wcore_info *t` to top scope in the function.
This prepares for the next commit, which adds support for POSIX platforms
without thread-local storage.

Signed-off-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@linux.intel.com>

waffle-gl/waffle,fjhenigman/waffle,yinquan529/waffle-gl-waffle,yinquan529/waffle-gl-waffle,maurossi/waffle,janesma/waffle,evelikov/waffle,janesma/waffle,chadversary/waffle,dcbaker/waffle,maurossi/waffle,waffle-gl/waffle,chadversary/waffle,janesma/waffle,waffle-gl/waffle,dcbaker/waffle,fjhenigman/waffle,chadversary/waffle,evelikov/waffle,waffle-gl/waffle,maurossi/waffle,dcbaker/waffle,yinquan529/waffle-gl-waffle,evelikov/waffle,fjhenigman/waffle