sysctl: Add optional range checking to SYSCTL_INT_CONV_CUSTOM

sysctl: Add optional range checking to SYSCTL_INT_CONV_CUSTOM

Extend the SYSCTL_INT_CONV_CUSTOM macro with a k_ptr_range_check
parameter to conditionally generate range validation code. When enabled,
validation is done against table->extra1 (min) and table->extra2 (max)
bounds before assignment. Add base minmax and ms_jiffies_minmax
converter instances that utilize the range checking functionality.

Signed-off-by: Joel Granados <joel.granados@kernel.org>