bash: add more security patches

Apply new patches for a buffer overflow fix (pl28) and an invalid memory
access (pl29).
Rename combined patchlevel patch to be more graphic about the range.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>