[LU-18163] Add a helper function to parse percent for memory value

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.17.0
• Severity: 3
• Assignee: Etienne Aujames
• Reporter: Etienne Aujames

Description

The sysfs_memparse() function parses strings for memory size. The string format is a decimal value followed by a unit suffix.
This ticket proposes to add a helper function to parse '%' unit and return the proportion of a total size.