Too many times have I mistyped the word

'install' as 'isntall'

Now this typo shall no longer be a problem since
'make isntall' just builds the 'install' target.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@145381 65c4cc65-6c06-0410-ace0-fbb531ad65f3