hang in crashtesting, would be nice to know what failed to exec here

 #0  0x00007f8dc781e4dc in __lll_lock_wait () from /lib64/libpthread.so.0
 #1  0x00007f8dc781a1b8 in _L_lock_820 () from /lib64/libpthread.so.0
 #2  0x00007f8dc781a088 in pthread_mutex_lock () from /lib64/libpthread.so.0
 #3  0x00007f8dc81d57d1 in lookupThreadId (hThread=140246229497600) at sal/osl/unx/thread.cxx:585
 #4  0x00007f8dc81d5aa4 in osl_getThreadIdentifier (Thread=0x0) at sal/osl/unx/thread.cxx:701
 #5  0x00007f8dc8173fa0 in osl::Thread::getCurrentIdentifier () at include/osl/thread.hxx:138
 #6  0x00007f8dc81736ba in sal_detail_log (level=SAL_DETAIL_LOG_LEVEL_WARN, area=0x7f8dc81f2e53 "sal.osl",
     where=0x7f8dc81f3130 "sal/osl/unx/process.cxx:238: ", message=0x5bd5b90 "Failed to exec: ENOENT", backtraceDepth=0)
     at sal/osl/all/log.cxx:279
 #7  0x00007f8dc816d166 in sal::detail::log (level=SAL_DETAIL_LOG_LEVEL_WARN, area=0x7f8dc81f2e53 "sal.osl",
     where=0x7f8dc81f3130 "sal/osl/unx/process.cxx:238: ", stream=..., backtraceDepth=0)
     at include/sal/log.hxx:50
 #8  0x00007f8dc81c1ddc in ChildStatusProc (pData=0x7f8d9e302a90) at sal/osl/unx/process.cxx:238
 #9  0x00007f8dc81d49a6 in osl_thread_start_Impl (pData=0x6757780) at sal/osl/unx/thread.cxx:235
 #10 0x00007f8dc7817f6b in start_thread () from /lib64/libpthread.so.0
 #11 0x00007f8dc7b227ed in clone () from /lib64/libc.so.6

Change-Id: I611cf907f89c7a1d8cdc3a9c42f449e8daaa2614
Reviewed-on: https://gerrit.libreoffice.org/69363
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

sal/osl/unx/process.cxx

@@ -235,9 +235,7 @@ static void ChildStatusProc(void *pData)
             execv(data.m_pszArgs[0], const_cast<char **>(data.m_pszArgs));
         }
 
-        SAL_WARN("sal.osl", "Failed to exec: " << UnixErrnoString(errno));
-
-        SAL_WARN("sal.osl", "ChildStatusProc : starting '" << data.m_pszArgs[0] << "' failed");
+        SAL_WARN("sal.osl", "ChildStatusProc : Failed to exec <" << data.m_pszArgs[0] << ">: " << UnixErrnoString(errno));
 
         /* if we reach here, something went wrong */
         errno_copy = errno;