gs1/gs1_lint: update to latest gs1-syntax-dictionary, removing

`iso3166list` linter and adjusting all others to allow for
  multiple optional linters (by checking `data_len` vs `offset`)
library: change invalid `input_mode` reset to return warning;
  split func table into 2 - func declarations without prototype
  will be error in C23;
  make invalid symbology check a separate function using a table
  and call near beginning of `ZBarcode_Encode_Segs()`;
  in `ZBarcode_BarcodeName()` save some bytes by simplifying
  name table and removing "BARCODE_" prefix from entries
output: fix pack logic to use pragma by default (actually more
  portable than `__attribute__`)
common.h: remove C99 detection which was artifice of specifying
  "-std=", and rejig layout to be more logical
BWIPP: update to latest version
general: change `ZINT_VERSION_BUILD` tests to `#if`s
general: further fiddling with some tables to save a few bytes
CLI: change function arg `optarg` -> `arg` so doesn't shadow
  global
general: library now compilable with Comp Cert C (though as it
  doesn't support `alloca()` will have multiple memory leaks)

backend/output.h

@@ -113,11 +113,13 @@ INTERNAL FILE *out_win_fopen(const char *filename, const char *mode);
         bp[3] = (unsigned char) ((*p_u32 >> 24) & 0xFF); \
     } while (0)
 
-/* For more portability, use `#pragma pack()` pair for MSCV, per-type packed attribute otherwise */
-#ifdef _MSC_VER
-#  define OUT_PACK
+/* If `#pragma pack()` not supported, try per-type packed attribute */
+#ifdef __COMPCERT__
+/* Can't use `__attribute__` as may be defined to be no-op by libc if not GNU C or Clang (e.g. glibc does this) */
+#  define OUT_PACK __attribute((__packed__)) /* CompCert C workaround extension `__attribute` */
 #else
-#  define OUT_PACK __attribute__((__packed__))
+#  define OUT_USE_PRAGMA_PACK
+#  define OUT_PACK
 #endif
 
 #ifdef __cplusplus