finish busybox.1 renaming

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/Makefile b/Makefile
index b7afaa9..c41643d 100644
--- a/Makefile
+++ b/Makefile
@@ -991,7 +991,7 @@
 
 PHONY += doc-clean
 doc-clean: rm-files := docs/busybox.pod \
-		  docs/BusyBox.html docs/BusyBox.1 docs/BusyBox.txt
+		  docs/BusyBox.html docs/busybox.1 docs/BusyBox.txt
 doc-clean:
 	$(call cmd,rmfiles)
 
diff --git a/docs/.gitignore b/docs/.gitignore
index 9d1b7c2..11d6163 100644
--- a/docs/.gitignore
+++ b/docs/.gitignore
@@ -1,4 +1,4 @@
-/BusyBox.1
+/busybox.1
 /BusyBox.html
 /BusyBox.txt
 /busybox.pod