5953ae56d8
During the Apple SDK revamp of #346043, cc-wrapper and bintools-wrapper
were modified to automatically add a fallback SDK if $DEVELOPER_DIR is
not set [^1]. However, because of the order of the && operands,
apple-sdk is always evaluated even when it's not needed.
Flip the && operands so we only trigger the evaluation when targeting
Darwin.
[^1]: 51755b0c00