omniorb: add patch to fix musl build

Fixes:

  http://autobuild.buildroot.net/results/0e2025cbc1c54f0c177ce3f27020d454aa03645a/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/omniorb/0001-fix-unistd-sys-time-includes.patch

@@ -0,0 +1,61 @@
+omniorb/thread: use proper autoconf macros for header inclusion
+
+src/lib/omnithread/posix.cc uses sleep() and usleep(), defined in
+<unistd.h> on numerous platforms, and struct timeval/gettimeofday(),
+defined in <sys/time.h> on various platforms.
+
+Since those header files are not available on all platforms, posix.cc
+currently uses the following condition:
+
+#if (defined(__GLIBC__) && __GLIBC__ >= 2) || defined(__SCO_VERSION__) || defined(__aix__) || defined (__cygwin__) || defined(__darwin__) || defined(__macos__)
+
+Unfortunately, this falls short on Linux systems based on the musl C
+library. Indeed, the musl C library does not define the __GLIBC__
+symbol, but does have the sleep()/usleep() definitions in <unistd.h>,
+and the struct timeval/gettimeofday() definitions in <sys/time.h>,
+like any Linux system. Also, the musl C library does not define any
+constant like __MUSL__ to distinguish it.
+
+Due to this, on musl based systems, <unistd.h> and <sys/time.h> are
+not included, causing a build failure:
+
+posix.cc:864:22: error: '::sleep' has not been declared
+       while ((secs = ::sleep(secs))) ;
+                      ^
+posix.cc:866:43: error: 'usleep' was not declared in this scope
+  usleep(secs * 1000000 + (nanosecs / 1000));
+                                           ^
+posix.cc: In static member function 'static void omni_thread::get_time(long unsigned int*, long unsigned int*, long unsigned int, long unsigned int)':
+posix.cc:904:20: error: aggregate 'omni_thread::get_time(long unsigned int*, long unsigned int*, long unsigned int, long unsigned int)::timeval tv' has incomplete type and cannot be defined
+     struct timeval tv;
+                    ^
+posix.cc:905:24: error: 'gettimeofday' was not declared in this scope
+     gettimeofday(&tv, 0); 
+
+It turns out that the configure.ac already checks for the availability
+of <unistd.h> and <sys/time.h>. So all what this patch does is use the
+C defines generated by the configure script to decide whether
+<unistd.h> and <sys/time.h> can be included or not.
+
+Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+
+Index: b/src/lib/omnithread/posix.cc
+===================================================================
+--- a/src/lib/omnithread/posix.cc
++++ b/src/lib/omnithread/posix.cc
+@@ -78,10 +78,14 @@
+ #include <errno.h>
+ #include <time.h>
+ #include <omnithread.h>
++#include <omniORB4/acconfig.h>
+ 
+-#if (defined(__GLIBC__) && __GLIBC__ >= 2) || defined(__SCO_VERSION__) || defined(__aix__) || defined (__cygwin__) || defined(__darwin__) || defined(__macos__)
+ // typedef of struct timeval and gettimeofday();
++#if defined(HAVE_SYS_TIME_H)
+ #include <sys/time.h>
++#endif
++
++#if defined(HAVE_UNISTD_H)
+ #include <unistd.h>
+ #endif
+