Fix unbounded stack in emberAfPrintBuffer()

[kpschoedel]

Problem

emberAfPrintBuffer() allocates stack space based on an argument, with
no upper bound. This could lead to stack exhaustion on small devices.

Summary of Changes

Print long buffers in multiple segments.

Fixes #3662 - Unbounded stack in emberAfPrintBuffer()

[andy31415]

Is there a way we could unit test this? Maybe add a TODO PR (I think I wanted to do app/util unit tests before and failed, so it does not seem fair to ask you do do it as part of this PR).

[kpschoedel]

Added TODO. I did verify the change out-of-tree with a #define emberAfPrint(c,...) printf(__VA_ARGS__).

[github-actions]

Size increase report for "esp32-example-build" from fcc0e36

File	Section	File	VM
chip-all-clusters-app.elf	.flash.text	16	16

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-all-clusters-app.elf and ./pull_artifact/chip-all-clusters-app.elf:

sections,vmsize,filesize
.debug_line,0,220
.debug_info,0,184
.debug_str,0,64
.debug_abbrev,0,54
.flash.text,16,16
.debug_ranges,0,-24
.debug_loc,0,-150

[github-actions]

Size increase report for "nrfconnect-example-build" from fcc0e36

File	Section	File	VM
chip-lock.elf	shell_root_cmds_sections	4	4
chip-lock.elf	text	-4	-4
chip-lighting.elf	shell_root_cmds_sections	4	4
chip-lighting.elf	text	-4	-4

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-lock.elf and ./pull_artifact/chip-lock.elf:

sections,vmsize,filesize
.debug_info,0,2291
.debug_line,0,486
.debug_abbrev,0,327
.debug_str,0,52
.debug_loc,0,28
shell_root_cmds_sections,4,4
text,-4,-4
.debug_frame,0,-8

Comparing ./master_artifact/chip-shell.elf and ./pull_artifact/chip-shell.elf:

sections,vmsize,filesize

Comparing ./master_artifact/chip-lighting.elf and ./pull_artifact/chip-lighting.elf:

sections,vmsize,filesize
.debug_info,0,2291
.debug_line,0,486
.debug_abbrev,0,327
.debug_str,0,52
.debug_loc,0,36
shell_root_cmds_sections,4,4
text,-4,-4
.debug_frame,0,-8