Bug 445128 - Stop putting the version number in the target directory for make install. r=nalexander

Back when I filed this bug, $appname-$version was already useless, but
there actually were multiple supported versions (e.g. 3.5/3.6). So it
made sense to have e.g. firefox-3.5 and firefox-3.6, but not
firefox-3.5.12 and firefox-3.5.13.

Fast forward 10 years, and we change "major" versions every 6 to 8
weeks, have multiple chemspills every other week, and installing to
firefox-57.0, firefox-57.0.1, firefox-57.0.2, firefox-57.0.3 doesn't
make any kind of sense. Even firefox-56, firefox-57 is pretty much
useless.

There /kind/ of was some usefulness to the version in the SDK
directories, but those are gone.

I'm pretty sure no downstream is actually using versioned directories
anyways.

At this point, it seems better to just use the application name, without
the version. A case could be made about ESR, but that would be better
handled with a separate application name (e.g. firefox-esr).

--HG--
extra : rebase_source : 333e10ea1316714bf0008ec772b35093edfc45ff

config/baseconfig.mk

@@ -2,7 +2,7 @@
 # directly in python/mozbuild/mozbuild/base.py for gmake validation.
 # We thus use INCLUDED_AUTOCONF_MK to enable/disable some parts depending
 # whether a normal build is happening or whether the check is running.
-installdir = $(libdir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
+installdir = $(libdir)/$(MOZ_APP_NAME)
 ifeq (.,$(DEPTH))
 DIST = dist
 else