conf: drop the angle brackets from if, infer from the value

The block format spells conditions as bare strings everywhere else, so
requiring `if = "<usr/foo>"` left one sigil behind, carried over from
the line-based `if:` token.  A namespace separator already tells the two
apart: a value with a '/' is a condition, anything else is a service
name.

svc_ifthen() picks its mode from the start of the statement and applies
it to the whole, so a statement naming both kinds cannot be evaluated.
That is now an error, as are the old angle brackets, and either one
skips the block:

    /etc/finit.conf: mixed: if: cannot mix a service name with a
    condition in 'anchor,usr/enable-me', a statement must be all of
    one kind, skipping

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

test/Makefile.am

@@ -32,6 +32,7 @@ EXTRA_DIST		+= add-remove-dynamic-service-sub-config.sh
 EXTRA_DIST		+= bootstrap-crash.sh
 EXTRA_DIST		+= cond-start-task.sh
 EXTRA_DIST		+= conf-format.sh
+EXTRA_DIST		+= conf-if.sh
 EXTRA_DIST		+= conf-template.sh
 EXTRA_DIST		+= script-timeout.sh
 EXTRA_DIST		+= crashing.sh
@@ -79,6 +80,7 @@ TESTS			+= add-remove-dynamic-service-sub-config.sh
 TESTS			+= bootstrap-crash.sh
 TESTS			+= cond-start-task.sh
 TESTS			+= conf-format.sh
+TESTS			+= conf-if.sh
 TESTS			+= conf-template.sh
 TESTS			+= script-timeout.sh
 TESTS			+= crashing.sh