make install in winsup

[Glenn Spell]

With the latest snapshots, without changes to Makefile.in, make
install fails in winsup if installing into a directory that's
included in $PATH because the DLL is installed as cygwin1.dll.

Should this be changed for the release?

-glenn

-- 
 )      Glenn Spell <glenn@gs.fay.nc.us>      )   _       _____
 )   Fayetteville, North Carolina, U. S. A.   )_ (__\____o /_/_ |
 )     _  _  _  _  _  _  _  _  _  _  _  _     )   >-----._/_/__]>
 )--- Cygwin - Don't leave Unix without it ---)             `0  |