fix: include limits.h for INT_MAX and INT_MIN

[chenrui333]

seeing some build failure against 1.5.4 release

 [ 83%] Building C object CMakeFiles/mbpoll.dir/src/utils.c.o
  /opt/homebrew/Library/Homebrew/shims/mac/super/clang -DNDEBUG -DSKIP_FAILURE_EXIT -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE -I/private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4 -I/private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src -I/private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/build -I/opt/homebrew/Cellar/libmodbus/3.1.11/include/modbus -O3 -DNDEBUG -arch arm64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk -Wall -Wextra -Wpedantic -Wformat-security -Wno-unused-parameter -Wno-unused-function -Wno-unused-const-variable -fstack-protector-strong -MD -MT CMakeFiles/mbpoll.dir/src/utils.c.o -MF CMakeFiles/mbpoll.dir/src/utils.c.o.d -o CMakeFiles/mbpoll.dir/src/utils.c.o -c /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/utils.c
  /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/mbpoll.c:623:30: error: use of undeclared identifier 'INT_MAX'
    623 |             if (start_addr > INT_MAX - unit_size_regs) {
        |                              ^
  /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/mbpoll.c:635:31: error: use of undeclared identifier 'INT_MAX'
    635 |               if (next_addr > INT_MAX - unit_size_regs) {
        |                               ^
  /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/mbpoll.c:643:31: error: use of undeclared identifier 'INT_MAX'
    643 |               if (next_addr > INT_MAX - unit_size_regs) {
        |                               ^
  /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/mbpoll.c:1350:33: error: use of undeclared identifier 'INT_MAX'
   1350 |   if (errno == ERANGE || lval > INT_MAX || lval < INT_MIN) {
        |                                 ^
  /private/tmp/mbpoll-20260209-4990-1ml6no/mbpoll-1.5.4/src/mbpoll.c:1350:51: error: use of undeclared identifier 'INT_MIN'
   1350 |   if (errno == ERANGE || lval > INT_MAX || lval < INT_MIN) {
        |                                                   ^
  5 errors generated.

• mbpoll 1.5.4 Homebrew/homebrew-core#266539

[Copilot]

Pull request overview

Fixes a macOS/Clang build failure in mbpoll 1.5.4 where INT_MAX/INT_MIN are referenced without including the standard header that defines them.

Changes:

• Add #include <limits.h> to ensure INT_MAX and INT_MIN are available during compilation.

---

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[epsilonrt]

Hi @chenrui333
As stated in the new mbpoll update policy (see the CONTRIBUTING file), pull requests must be submitted against the dev branch.
Thank you for your contribution.

[chenrui333]

As stated in the new mbpoll update policy (see the CONTRIBUTING file), pull requests must be submitted against the dev branch.

Sorry, I missed it (would it better to make dev branch as default branch? what do you think?)