env: Remove include/generated/env.* under "make clean"

When running "make clean" we want to remove env.in and well as env.txt.

Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/Makefile b/Makefile
index 9575d43..93571d3 100644
--- a/Makefile
+++ b/Makefile
@@ -2207,7 +2207,7 @@
 			$(filter-out include, $(shell ls -1 $d 2>/dev/null))))
 
 CLEAN_FILES += include/bmp_logo.h include/bmp_logo_data.h \
-	       include/generated/env.in drivers/video/u_boot_logo.S \
+	       include/generated/env.* drivers/video/u_boot_logo.S \
 	       tools/version.h u-boot* MLO* SPL System.map fit-dtb.blob* \
 	       u-boot-ivt.img.log u-boot-dtb.imx.log SPL.log u-boot.imx.log \
 	       lpc32xx-* bl31.c bl31.elf bl31_*.bin image.map tispl.bin* \