The template "Template Module HOST-RESOURCES-MIB SNMPv2" filters on specific filesystem parameters, but fails to exclude /dev, /sys and /run. Many people are jumping through loopholes to fix this, and the setting "Storage devices for SNMP discovery" in the Administration section of "regular expressions" doesn't apply.
Adding an extra filter to the Storage discovery with:
does not match
solves this (see this attachment: zbx_export_templates.xml )