text/template: reduce maxExecDepth for gccgo

text/template: reduce maxExecDepth for gccgo

    When using gccgo on systems without full support for split stacks a
    recursive template can overrun the available stack space.  Reduce the
    limit from 100000 to 10000 to make this less likely.  It's still high
    enough that real uses will work.

    Reviewed-on: https://go-review.googlesource.com/25467

From-SVN: r239141