Rename doc to docs

Makefile

@@ -1,6 +1,6 @@
 .POSIX:
 .SUFFIXES:
-.SUFFIXES: .1 .1.scd
+.SUFFIXES: .1.scd .1
 
 _git_version=$(shell git describe --tags --dirty 2>/dev/null)
 ifeq ($(strip $(_git_version)),)
@@ -13,18 +13,14 @@ PREFIX?=/usr/local
 BINDIR?=$(PREFIX)/bin
 MANDIR?=$(PREFIX)/share/man
 
-VPATH=doc
 GO?=go
 GOFLAGS?=
 GOSRC!=find . -name '*.go'
 GOSRC+=go.mod go.sum
 
-DOCS := \
-	kiln.1
+all: kiln docs
 
-all: kiln doc
-
-doc: $(DOCS)
+docs: docs/kiln.1
 
 .1.scd.1:
 	scdoc < $< > $@
@@ -41,10 +37,10 @@ clean:
 install: all
 	mkdir -p $(DESTDIR)$(BINDIR) $(DESTDIR)$(MANDIR)/man1
 	install -m755 kiln $(DESTDIR)$(BINDIR)/kiln
-	install -m755 kiln.1 $(MANDIR)/man1/kiln.1
+	install -m755 docs/kiln.1 $(MANDIR)/man1/kiln.1
 
 uninstall:
 	$(RM) $(DESTDIR)$(BINDIR)/kiln
 	$(RM) $(DESTDIR)$(MANDIR)/man1/kiln.1
 
-.PHONY: all doc clean install uninstall
+.PHONY: all docs clean install uninstall