scripts: ath10k-check: fix nproc command
scripts: ath10k-check: fix nproc command

For testing purposes I had used 'nproc2' but forgot to change that before
commit.

Signed-off-by: Kalle Valo <7081a7d99b8c74c0698a728df19e3915a995d7e1@qca.qualcomm.com>

qca/qca-swiss-army-knife,qca/qca-swiss-army-knife,qca/qca-swiss-army-knife,qca/qca-swiss-army-knife