scsi: ufs: export some functions for vendor usage

scsi: ufs: export some functions for vendor usage

Export below functions for vendor usage:

int ufshcd_hba_enable(struct ufs_hba *hba);
int ufshcd_make_hba_operational(struct ufs_hba *hba);
int ufshcd_uic_hibern8_exit(struct ufs_hba *hba);

Link: https://lore.kernel.org/r/20200117035108.19699-3-stanley.chu@mediatek.com
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>