[R] Fix guard around dataset___Scanner__TakeRows

[asfimport]

ARROW-11797 / #9589 wrapped a Dataset-dependent function definition in #if defined(ARROW_R_WITH_ARROW)  instead of #if defined(ARROW_R_WITH_DATASET), causing R minimal builds to fail

d575858#diff-f6ded32632f8b1516f0e852b8e648af02be39e60010c546a17502d1830245076R2085

 

Reporter: Ian Cook / @ianmcook
Assignee: Ian Cook / @ianmcook

PRs and other links:

• GitHub Pull Request #10051

_{Note: This issue was originally created as ARROW-12401. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
Issue resolved by pull request 10051
#10051