C89 compliance items

[anhu]

Fixes ZD 22098

• Flexible array members ("type name[];") fixup
• avoid empty asn_orig.c when building standalone
• avoid trailing comma on the last enumerator
• drop some consts to match function prototypes

[github-actions]

MemBrowse Memory Report

gcc-arm-cortex-m0plus

• FLASH: .text +64 B (+0.1%, 64,155 B / 262,144 B, total: 24% used)

gcc-arm-cortex-m3

• FLASH: .text +268 B (+0.2%, 122,449 B / 262,144 B, total: 47% used)

gcc-arm-cortex-m4

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B, .text +320 B (+0.2%, 200,284 B / 262,144 B, total: 76% used)

gcc-arm-cortex-m4-baremetal

• FLASH: .text +64 B (+0.1%, 66,763 B / 262,144 B, total: 25% used)

gcc-arm-cortex-m4-crypto-only

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B, .text +64 B (+0.1%, 174,440 B / 262,144 B, total: 67% used)

gcc-arm-cortex-m4-dtls13

• FLASH: .text +192 B (+0.1%, 180,824 B / 1,048,576 B, total: 17% used)

gcc-arm-cortex-m4-min-ecc

• FLASH: .text +64 B (+0.1%, 61,741 B / 262,144 B, total: 24% used)

gcc-arm-cortex-m4-openssl-compat

• FLASH: .rodata +248 B, .text +1,024 B (+0.2%, 770,764 B / 1,048,576 B, total: 74% used)

gcc-arm-cortex-m4-pkcs7

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B (+0.0%, 212,268 B / 262,144 B, total: 81% used)

gcc-arm-cortex-m4-pq

• FLASH: .rodata +60 B, .text +192 B (+0.1%, 279,236 B / 1,048,576 B, total: 27% used)

gcc-arm-cortex-m4-rsa-only

• FLASH: .rodata +56 B, .text +256 B (+0.1%, 324,896 B / 1,048,576 B, total: 31% used)

gcc-arm-cortex-m4-sp-math

• FLASH: .text +64 B (+0.1%, 61,741 B / 262,144 B, total: 24% used)

gcc-arm-cortex-m4-tls12

• FLASH: .text +256 B (+0.2%, 123,213 B / 262,144 B, total: 47% used)

gcc-arm-cortex-m4-tls13

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B, .text +128 B (+0.1%, 235,918 B / 262,144 B, total: 90% used)

gcc-arm-cortex-m7

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B, .text +320 B (+0.2%, 200,220 B / 262,144 B, total: 76% used)

gcc-arm-cortex-m7-pq

• FLASH: .rodata +60 B, .text +192 B (+0.1%, 279,812 B / 1,048,576 B, total: 27% used)

gcc-arm-cortex-m7-tls13

• FLASH: .rodata.CSWTCH.1 +4 B, .rodata.str1.1 +58 B, .text +192 B (+0.1%, 235,982 B / 262,144 B, total: 90% used)

linuxkm-pie

• Data: __patchable_function_entries +136 B (+0.5%, 25,456 B)

linuxkm-standard

• Data: __patchable_function_entries +160 B (+0.3%, 48,112 B)

stm32-sim-stm32h753

• FLASH: .text +320 B (+0.2%, 183,396 B / 2,097,152 B, total: 9% used)

[douzzer]

This needs to be named WC_FLEXIBLE_ARRAY_SIZE. It also needs override capability. The setup for it in WolfSentry is

#if defined(WOLFSENTRY_FLEXIBLE_ARRAY_SIZE)
    /* keep override value. */
#elif defined(__STRICT_ANSI__) || defined(WOLFSENTRY_PEDANTIC_C)
    #define WOLFSENTRY_FLEXIBLE_ARRAY_SIZE 1
#elif defined(__GNUC__) && !defined(__clang__)
    #define WOLFSENTRY_FLEXIBLE_ARRAY_SIZE
    /*!< \brief Value appropriate as a size for an array that will be allocated to a variable size.  Built-in value usually works. */
#else
    #define WOLFSENTRY_FLEXIBLE_ARRAY_SIZE 0
#endif

and that's my recommendation here too, with || defined(WOLF_C89) added to the __STRICT_ANSI__ condition.

[douzzer]

Note a whitespace flub in the reindented comments in the struct ExternalTicket definition -- but def not worth holding up the PR for it.

[anhu]

Fixed the whitespace.