clang-5.0 is not supported. Please use one of the following versions

Hi L4 hackers,

I am using clang (svn trunk 303321) to build fiasco, it thrown such 
error: kernel/fiasco/src/Makeconf:264: *** clang-5.0 is not supported. 
Please use one of the following versions: 3.5 3.6 3.7 3.8

so I simply add other versions for clang, please review my patch, thanks 
a lot!


Index: kernel/fiasco/src/Makeconf
===================================================================
--- kernel/fiasco/src/Makeconf  (revision 72)
+++ kernel/fiasco/src/Makeconf  (working copy)
@@ -245,7 +245,7 @@


  CC_WHITELIST-gcc     := 4.5 4.6 4.7 4.8 4.9 5 6
-CC_WHITELIST-clang   := 3.5 3.6 3.7 3.8
+CC_WHITELIST-clang   := 3.5 3.6 3.7 3.8 3.9 4.0 5.0
  CC_WHITELIST         := $(CC_WHITELIST-$(CC_TYPE))

  CC_BLACKLIST-arm-gcc   := 4.8.0 4.8.1 4.8.2


-- 
Regards,
Leslie Zhai https://reviews.llvm.org/p/xiangzhai/