Up the character limit for thermal strings

Some thermal strings needed for warning users
when their phone shut down due to overheating
were too hard to translate with the set char
limit. This CL ups the char limit to allow for
easier translation of this strings.

Test: Manual, see screenshot in comments
Bug: 37452341, 37452235
Change-Id: I5a9e24f413a759d83911a1054da8bfce222cfe9a