The generated assembly emitted <name>_length immediately after the raw
payload bytes, so the 32-bit word landed misaligned whenever the data
size was not a multiple of 4. Consumers declare it as a 32-bit object
(e.g. `extern const size_t <name>_length` in the ULP firmware loaders),
so the compiler emits an alignment-assuming word load, which is a
misaligned flash read prone to spurious load faults on chips with
SOC_CPU_MISALIGNED_ACCESS_ON_PMP_MISMATCH_ISSUE (ESP32-C6/H2/H21).
Newer GNU bin-utils version 2.39 has started emitting a warning
about an executable stack region for Linux target build:
/usr/bin/ld: warning: x509_crt_bundle.S.o: missing .note.GNU-stack section implies executable stack
Fix the issue by adding appropriate "noexecute" attribute for stack
section.
For Linux builds if the embedded data length exceeded 16-bit value then
the build used to fail with following error:
build/x509_crt_bundle.S: Assembler messages:
build/x509_crt_bundle.S:4201: Warning: value 0x1056e truncated to 0x56e
GNU ASM for X86 systems treats .word attribute as of size 2 bytes, this commit
uses .long attribute to take the size to 4 bytes.
