ARM: Set bit 0 for thumb mode in kallsyms_lookup_name returned address

This patch fixes the undefined instruction oops due to execution
of thumb-2 code in ARM mode. The zero bit in the symbol address
returned by kallsyms_lookup_name is not set, leading to switching
to ARM mode that generates oops while executing thumb-2 code. For
detailed discussion, see [1].
[1] http://lists.casi.polymtl.ca/pipermail/ltt-dev/2011-September/005176.html

v1:
        - include wrapper function kallsyms_lookup_funcptr as suggested
        by Dave Martin

Signed-off-by: Avik Sil <avik.sil@linaro.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>