MokManager: Fix a conditional on an uninitialized value in one error path.
MokManager: Fix a conditional on an uninitialized value in one error path.

clang-analyzer says:

MokManager.c:1431:6: warning: Branch condition evaluates to a garbage value
        if (mok)
            ^~~
MokManager.c:1433:6: warning: Branch condition evaluates to a garbage value
        if (del_key)
            ^~~~~~~

And it's right; if we take the first error exit in the function, those
never get initialized.  This patch sets them to NULL to begin with.

Signed-off-by: Peter Jones <2e0a021e603479ff81838c00c3b770daca4e0214@redhat.com>

rhinstaller/shim,rhinstaller/shim,rhinstaller/shim