watch_variable: Remove excess access type

The ALLOWED_UNKNOWN_VARIABLE_READ_ACCESS access type was switched on an
undocumented variable and its lookup caused an unnecessary performance
impact.
Merge topic 'dev/watch-variable-allowed-access-type' into next

81711724 watch_variable: Remove excess access type
watch_variable: Remove excess access type

The ALLOWED_UNKNOWN_VARIABLE_READ_ACCESS access type was switched on an
undocumented variable and its lookup caused an unnecessary performance
impact.
Merge topic 'dev/watch-variable-allowed-access-type' into next

daa854c7 watch_variable: Remove excess access type