EQUAL compares numeric values. Use STREQUAL instead.

Also clarify the macro for setting the export map / version script.

Bug b/110884149

Change-Id: If30c31d17ad35684a8c637b3619bdd0b90be6f2d
Reviewed-on: https://swiftshader-review.googlesource.com/19709Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>