Set the bootstrap profile to v4.7.1
--- a/mcs/build/profiles/build.make
+++ b/mcs/build/profiles/build.make
@@ -42,7 +42,7 @@
 
 PROFILE_MCS_FLAGS = -d:NET_4_0 -d:NET_4_5 -d:MONO -d:WIN_PLATFORM -d:BOOTSTRAP_BASIC -nowarn:1699 -nostdlib
 API_BIN_PROFILE = v4.7.1
-BOOTSTRAP_BIN_PROFILE = v4.7
+BOOTSTRAP_BIN_PROFILE = v4.7.1
 
 NO_SIGN_ASSEMBLY = yes
 NO_TEST = yes