Removed redundant call to find_energy_index.
Removed redundant call to find_energy_index.

shikhar413/openmc,wbinventor/openmc,nhorelik/openmc,liangjg/openmc,keadyk/openmc_mg_prepush,mjlong/openmc,lilulu/openmc,mit-crpg/openmc,amandalund/openmc,shikhar413/openmc,smharper/openmc,smharper/openmc,shenqicang/openmc,nhorelik/openmc,smharper/openmc,walshjon/openmc,keadyk/openmc_mg_prepush,mit-crpg/openmc,mit-crpg/openmc,johnnyliu27/openmc,walshjon/openmc,mit-crpg/openmc,liangjg/openmc,shikhar413/openmc,smharper/openmc,wbinventor/openmc,samuelshaner/openmc,kellyrowland/openmc,paulromano/openmc,lilulu/openmc,keadyk/openmc_mg_prepush,amandalund/openmc,lilulu/openmc,liangjg/openmc,johnnyliu27/openmc,shenqicang/openmc,bhermanmit/cdash,paulromano/openmc,samuelshaner/openmc,walshjon/openmc,johnnyliu27/openmc,mjlong/openmc,walshjon/openmc,paulromano/openmc,wbinventor/openmc,samuelshaner/openmc,samuelshaner/openmc,sxds/opemmc,shikhar413/openmc,wbinventor/openmc,amandalund/openmc,bhermanmit/openmc,sxds/opemmc,bhermanmit/openmc,kellyrowland/openmc,liangjg/openmc,paulromano/openmc,johnnyliu27/openmc,amandalund/openmc