Move langInfo.txt regeneration away from updatecldrdata.py

The regeneration tool depends on ICU4J, and thus the data
ICU4J data resources files need to be regenerated before
generating langInfo.txt.

Thus, the regeneration step from updatecldrdata.py to
updateicudata.py

Test: tools/updateicudata.py
Change-Id: I947c8e277796126c3abbc803a74c9e8a50887f9a
3 files changed