devel/objconv: update to 2.54

• fix problem with ELF files having same string table for symbols and sections (generated by rustc compiler).

PR: 266187
Reported by: fuz@fuz.su (mantoainer)
MFH: 2022Q3 (bugfix)

(cherry picked from commit f239f50b9827c18ed9edc3bb486a4dcbadac59ad)