jb/linker.c: allow debug of the linker and hooked symbols

Signed-off-by: Ricardo Salveti de Araujo <ricardo.salveti@canonical.com>
jb/linker.c: reduce debugging output for prelinked libraries

Not to worry much about the messages as it's not supported by latest
Android version anymore.

Signed-off-by: Ricardo Salveti de Araujo <ricardo.salveti@canonical.com>
Merge pull request #79 from rsalveti/linker-debug

Extend Linker Debug Support