Makefile: Add new "install-bash" target for bash completion support

It was problematic to have this in "make install" since it would
unconditionally try to install to /etc, (even if a non-privileged user
was attempting an install to a prefix in the user's home directory,
for example).

Makefile

@@ -19,6 +19,8 @@ ifeq ($(emacs_lispdir),)
 	emacs_lispdir = $(prefix)/share/emacs/site-lisp
 endif
 
+bash_completion_dir = /etc/bash_completion.d
+
 all_deps = Makefile Makefile.local Makefile.config \
 		   lib/Makefile lib/Makefile.local
 

Makefile.local

@@ -29,15 +29,12 @@ notmuch.1.gz: notmuch.1
 	$(call quiet,gzip) --stdout $^ > $@
 
 install: all notmuch.1.gz
-	for d in $(DESTDIR)$(prefix)/bin/ $(DESTDIR)$(prefix)/share/man/man1 \
-		$(DESTDIR)$(bash_completion_dir) ; \
+	for d in $(DESTDIR)$(prefix)/bin/ $(DESTDIR)$(prefix)/share/man/man1 ; \
 	do \
 		install -d $$d ; \
 	done ;
 	install notmuch $(DESTDIR)$(prefix)/bin/
 	install -m0644 notmuch.1.gz $(DESTDIR)$(prefix)/share/man/man1/
-	install contrib/notmuch-completion.bash \
-		$(DESTDIR)$(bash_completion_dir)/notmuch
 
 install-emacs: install emacs
 	for d in $(DESTDIR)/$(emacs_lispdir) ; \
@@ -47,5 +44,10 @@ install-emacs: install emacs
 	install -m0644 notmuch.el $(DESTDIR)$(emacs_lispdir)
 	install -m0644 notmuch.elc $(DESTDIR)$(emacs_lispdir)
 
+install-bash:
+	install -d $(DESTDIR)$(bash_completion_dir)
+	install contrib/notmuch-completion.bash \
+		$(DESTDIR)$(bash_completion_dir)/notmuch
+
 SRCS  := $(SRCS) $(notmuch_client_srcs)
 CLEAN := $(CLEAN) notmuch $(notmuch_client_modules) notmuch.elc notmuch.1.gz

configure

@@ -133,6 +133,5 @@ EOF
 # construct the Makefile.config
 cat > Makefile.config <<EOF
 prefix = /usr/local
-bash_completion_dir = /etc/bash_completion.d
 CFLAGS += ${have_valgrind}
 EOF