libs/utils/android: allow percentage arguments for tap
libs/utils/android: allow percentage arguments for tap

Signed-off-by: Michele Di Giorgio <99fd0b6f5a4e02a4022988691284da2a0299b046@arm.com>

credp/lisa,ARM-software/lisa,credp/lisa,arnoldlu/lisa,mdigiorgio/lisa,mdigiorgio/lisa,joelagnel/lisa,ARM-software/lisa,bjackman/lisa,credp/lisa,ARM-software/lisa,ARM-software/lisa,JaviMerino/lisa,bjackman/lisa,credp/lisa,arnoldlu/lisa,joelagnel/lisa