Makefile.uk: Restrict private headers to -iquote

All of libuuid's private headers are included using quotes.
This change therefore restricts the private include path to quote
includes only, to avoid inadvertent overinclusion.

Signed-off-by: Andrei Tatar <andrei@unikraft.io>
Reviewed-by: Stefan Jumarea <stefanjumarea02@gmail.com>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
GitHub-Closes: #6

Makefile.uk

@@ -64,7 +64,7 @@ CINCLUDES-$(CONFIG_LIBUUID) += -I$(LIBUUID_BUILD)/include/public
 # in a private folder and export that only locally to libuuid. The prepare
 # step below takes care of populating the folder
 $(call mk_sub_libbuild_dir,libuuid,include/private)
-LIBUUID_CINCLUDES-y += -I$(LIBUUID_BUILD)/include/private
+LIBUUID_CINCLUDES-y += -iquote$(LIBUUID_BUILD)/include/private
 
 ################################################################################
 # Global flags