doc: fix doxygen EXCLUDE

Add backspace and fix spacing.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

doc/zephyr.doxyfile

diff --git a/doc/zephyr.doxyfile b/doc/zephyr.doxyfile
index 8a01fa3..f526ec0 100644
--- a/doc/zephyr.doxyfile
+++ b/doc/zephyr.doxyfile
@@ -113,8 +113,8 @@
 INPUT_ENCODING         = UTF-8
 FILE_PATTERNS          = "*.c" "*.h" "*.S"
 RECURSIVE              = YES
-EXCLUDE                = ../include/spi_legacy.h
-             ../include/net/http_legacy.h \
+EXCLUDE                = ../include/spi_legacy.h \
+			 ../include/net/http_legacy.h \
 			 ../include/misc/util.h
 EXCLUDE_SYMLINKS       =
 EXCLUDE_PATTERNS       =