consolemap: Fix a memory leaking bug in drivers/tty/vt/consolemap.c

In function con_insert_unipair(), when allocation for p2 and p1[n]
fails, ENOMEM is returned, but previously allocated p1 is not freed,
remains as leaking memory. Thus we should free p1 as well when this
allocation fails.

Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>