add build-time support for module signing using native Linux facility;
add support for alternative licenses using WOLFSSL_LICENSE macro;
improve load-time kernel log messages;
add support for sp-math-all asm/AVX2 acceleration;
add error-checking and return in SAVE_VECTOR_REGISTERS();
implement support for x86 accelerated crypto from interrupt handlers, gated on WOLFSSL_LINUXKM_SIMD_X86_IRQ_ALLOWED:
* wolfcrypt_irq_fpu_states
* am_in_hard_interrupt_handler()
* allocate_wolfcrypt_irq_fpu_states()
* free_wolfcrypt_irq_fpu_states()
* save_vector_registers_x86()
* restore_vector_registers_x86()
add WOLFSSL_LINUXKM_SIMD, WOLFSSL_LINUXKM_SIMD_X86, and WOLFSSL_LINUXKM_SIMD_ARM macros for more readable gating.
* Adds `--enable-linuxkm-pie` and associated infrastructure, to support FIPS mode in the Linux kernel module.
* Adds `tests/api.c` missing (void) arglist to `test_SSL_CIPHER_get_xxx()`.
