Merge pull request #7326 from hashicorp/allow_to_set_build_settings

scripts/build.sh: allow to set build settings when building

scripts/build.sh

@@ -2,8 +2,8 @@
 
 # This script builds the application from source for multiple platforms.
 # Determine the arch/os combos we're building for
-ALL_XC_ARCH="386 amd64 arm arm64 ppc64le"
-ALL_XC_OS="linux darwin windows freebsd openbsd solaris"
+ALL_XC_ARCH=${ALL_XC_ARCH:-"386 amd64 arm arm64 ppc64le"}
+ALL_XC_OS=${ALL_XC_OS:-"linux darwin windows freebsd openbsd solaris"}
 
 # Exit immediately if a command fails
 set -e