[LU-373] port bug20355 to master(lctl and lfs need $(PTHREAD_LIBS))

• Type: Bug
• Resolution: Won't Fix
• Priority: Minor
• Fix Version/s: Lustre 2.1.0
• Affects Version/s: Lustre 2.1.0
• Severity: 3
• Bugzilla ID: 20,355
• Assignee: Hongchao Zhang
• Reporter: Hongchao Zhang

Description

on BG/P platform in LLNL, its compiler tool can't detect the pthread support implicitly, then it report compiler error.
the fix is adding the pthread support(CFLAGS, LIBS) according to the platform for the argument could be different in some platforms
(e.g. -lpthread or -lpthreads)

now the patch has been reverted in both b1_8 and master