pkg/56511: Add strnlen as msising feature on Solaris != 5.11

[pekdon%gmail.com@localhost]

>Number:         56511
>Category:       pkg
>Synopsis:       Add strnlen as msising feature on Solaris != 5.11
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 19 12:45:01 +0000 2021
>Originator:     Claes Nästén
>Release:        trunk 2021-11-18
>Organization:
>Environment:
SunOS 5.10 i86pc i386 i86pc
>Description:
strnlen is missing on Solaris 10 and earlier, but is not marked as such in SunOS.mk causing packages such as audio/lame fail in linking due to unresolved symbols.
>How-To-Repeat:
Build audio/lame
>Fix:
--- mk/platform/SunOS.mk.orig   Fri Nov 19 13:22:53 2021
+++ mk/platform/SunOS.mk        Fri Nov 19 13:37:23 2021
@@ -72,6 +72,9 @@
 .if !exists(/usr/include/err.h)
 _OPSYS_MISSING_FEATURES+=err
 .endif
+.if ${OS_VARIANT} == "Solaris" && ${OS_VERSION} != "5.11"
+_OPSYS_MISSING_FEATURES+=strnlen
+.endif
 _PATCH_CAN_BACKUP=     yes             # native patch(1) can make backups
 _PATCH_BACKUP_ARG?=    -b -V simple -z # switch to patch(1) for backup suffix
 _USE_RPATH=            yes             # add rpath to LDFLAGS