scripts/bloat-o-meter: switch argument parsing to using argparse

This will facilitate further extension to the arguments the script takes. 
As an added benefit it also produces saner usage output, where mutual
exclusivity of the c|d|t parameters is clearly visible:

./scripts/bloat-o-meter  -h
usage: bloat-o-meter [-h] [-c | -d | -t] file1 file2

Simple script used to compare the symbol sizes of 2 object files

positional arguments:
  file1       First file to compare
  file2       Second file to compare

optional arguments:
  -h, --help  show this help message and exit
  -c          categorize output based on symbol type
  -d          Show delta of Data Section
  -t          Show delta of text Section

Link: https://lkml.kernel.org/r/20220701113513.1938008-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/bloat-o-meter

@@ -7,18 +7,20 @@
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
-import sys, os, re
+import sys, os, re, argparse
 from signal import signal, SIGPIPE, SIG_DFL
 
 signal(SIGPIPE, SIG_DFL)
 
-if len(sys.argv) < 3:
-    sys.stderr.write("usage: %s [option] file1 file2\n" % sys.argv[0])
-    sys.stderr.write("The options are:\n")
-    sys.stderr.write("-c	categorize output based on symbol type\n")
-    sys.stderr.write("-d	Show delta of Data Section\n")
-    sys.stderr.write("-t	Show delta of text Section\n")
-    sys.exit(-1)
+parser = argparse.ArgumentParser(description="Simple script used to compare the symbol sizes of 2 object files")
+group = parser.add_mutually_exclusive_group()
+group.add_argument('-c', help='categorize output based on symbol type', action='store_true')
+group.add_argument('-d', help='Show delta of Data Section', action='store_true')
+group.add_argument('-t', help='Show delta of text Section', action='store_true')
+parser.add_argument('file1', help='First file to compare')
+parser.add_argument('file2', help='Second file to compare')
+
+args = parser.parse_args()
 
 re_NUMBER = re.compile(r'\.[0-9]+')
 
@@ -77,9 +79,9 @@ def calc(oldfile, newfile, format):
     delta.reverse()
     return grow, shrink, add, remove, up, down, delta, old, new, otot, ntot
 
-def print_result(symboltype, symbolformat, argc):
+def print_result(symboltype, symbolformat):
     grow, shrink, add, remove, up, down, delta, old, new, otot, ntot = \
-    calc(sys.argv[argc - 1], sys.argv[argc], symbolformat)
+    calc(args.file1, args.file2, symbolformat)
 
     print("add/remove: %s/%s grow/shrink: %s/%s up/down: %s/%s (%s)" % \
           (add, remove, grow, shrink, up, -down, up-down))
@@ -93,13 +95,13 @@ def print_result(symboltype, symbolformat, argc):
         percent = 0
     print("Total: Before=%d, After=%d, chg %+.2f%%" % (otot, ntot, percent))
 
-if sys.argv[1] == "-c":
-    print_result("Function", "tT", 3)
-    print_result("Data", "dDbB", 3)
-    print_result("RO Data", "rR", 3)
-elif sys.argv[1] == "-d":
-    print_result("Data", "dDbBrR", 3)
-elif sys.argv[1] == "-t":
-    print_result("Function", "tT", 3)
+if args.c:
+    print_result("Function", "tT")
+    print_result("Data", "dDbB")
+    print_result("RO Data", "rR")
+elif args.d:
+    print_result("Data", "dDbBrR")
+elif args.t:
+    print_result("Function", "tT")
 else:
-    print_result("Function", "tTdDbBrR", 2)
+    print_result("Function", "tTdDbBrR")