gh-112301: -fstack-protector-strong is also needed in LDFLAGS on Solaris/Illumos

[kulikjak]

Linker on Solaris/Illumos is unhappy when you pass -fstack-protector-strong flag via CFLAGS but not LDFLAGS, resulting in the following failure after #120975:

Undefined			first referenced
 symbol  			    in file
__stack_chk_fail                    Programs/_freeze_module.o
__stack_chk_guard                   Programs/_freeze_module.o
ld: fatal: symbol referencing errors

I don't think that other links will mind, but I can certainly make this into a Solaris/Illumos specific LDFLAGS append.

• Issue: Consider applying flags for warnings about potential security issues #112301

[corona10]

see: #121996 (comment)