Fix buildkey for GCC >= 7 if the version is listed including minor numbers.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

configure

@@ -2828,7 +2828,7 @@ g++*)
     3.*)
 	COMPILER_VERSION="3.*"
 	;;
-    [1-9][0-9]|[7-9]|[4-6].*)
+    [1-9][0-9]|[1-9][0-9].*|[7-9]|[4-9].*)
 	COMPILER_VERSION="4.*"
 	;;
     *)