find-provides.ksyms, find-requires.ksyms: rewrite section data matching
    
    Currently, it just matches the 2nd to 5th fields with awk, which leads
    to occasional capturing of some garbage at the end of the section data
    and minor issues when supplying it to the symbol extracting awk script:
    
        awk: cmd. line:1: (FILENAME=- FNR=19) fatal: argument index with `$' must be > 0
        awk: warning: escape sequence `\.' treated as plain `.'
        awk: cmd. line:1: (FILENAME=- FNR=9) fatal: not enough arguments to satisfy format string
        	`78b624dbc125415351be965ex.$..%ASQ..^'
        	                              ^ ran out for this one
    
    While at it, also eliminate grep and sed calls (with the pair of awk and
    sed being the most offending).
    
    * find-provides.ksyms: Generate part of the awk script that performs
    the byte reversal based on the endianness in the readelf -h output,
    inject it into the awk script;  use substr for matching parts
    of the section data instead of fields.
    * find-requires.ksyms (all_provides): Likewise.
    
    Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>