build/darwin_bni: Remove consistency check I added, I forgot we always load
every platform (even if it isn't being built).

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@144740 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/make/platform/darwin_bni.mk b/make/platform/darwin_bni.mk
index eddac8b..477e072 100644
--- a/make/platform/darwin_bni.mk
+++ b/make/platform/darwin_bni.mk
@@ -6,9 +6,6 @@
 # We override this with RC_ARCHS because B&I may want to build on an ARCH we
 # haven't explicitly defined support for. If all goes well, this will just work
 # and the resulting lib will just have generic versions for anything unknown.
-ifndef RC_ARCHS
-$(error "unexpected build of 'darwin_bni' platform without RC_ARCHS set")
-endif
 UniversalArchs := $(RC_ARCHS)
 
 ifneq (,$(SDKROOT))