Add an INLINE[n] or NOINLINE[n] pragma on mappendUpdateIO

[Mitsutoshi Aoe]

GHC 7.10 complains as follows:

FRP/Euphoria/Update.hs:108:11: Warning:
    Rule "mappendUpdateIO/()" may never fire
      because ‘mappendUpdateIO’ might inline first
    Probable fix: add an INLINE[n] or NOINLINE[n] pragma on ‘mappendUpdateIO’

Incidentally we have several warnings after AMP in the tests.