Commit 00fc0e0dda ("alpha: move exports to actual definitions") also
removed the exports of the math emulator hooks, which are defined in C
code. In case anyone cares about the option of CONFIG_MATHEMU=m, add
exports next to those definitions. Also add a MODULE_LICENSE.
Fixes: 00fc0e0dda ("alpha: move exports to actual definitions")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Matt Turner <mattst88@gmail.com>
