[OpenMP][FIX] Do not adjust the level after the environment was popped

Exiting a data environment will reset all values, it is wrong to adjust
them afterwards.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D112144

GitOrigin-RevId: 5102c3c61e266b533619644bb8eb27cecd26bfca
1 file changed