libunwind: add support for loongarch64

Modify package depends to allow building for loongarch64.
Also fix for building with musl.

Signed-off-by: Weijie Gao <hackpascal@gmail.com>

package/libs/libunwind/Makefile

@@ -32,7 +32,7 @@ define Package/libunwind
   CATEGORY:=Libraries
   TITLE:=The libunwind project
   URL:=http://www.nongnu.org/libunwind/
-  DEPENDS:=@((mips||mipsel||mips64||powerpc64||x86_64||arm||aarch64)||(USE_GLIBC&&(powerpc||i386))) +zlib
+  DEPENDS:=@((mips||mipsel||mips64||powerpc64||x86_64||arm||aarch64||loongarch64)||(USE_GLIBC&&(powerpc||i386))) +zlib
   ABI_VERSION:=8
 endef
 

package/libs/libunwind/patches/005-loongarch64-musl.pattch

@@ -0,0 +1,12 @@
+--- a/src/loongarch64/getcontext.S
++++ b/src/loongarch64/getcontext.S
+@@ -25,7 +25,9 @@ OF CONTRACT, TORT OR OTHERWISE, ARISING
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
+ 
+ #include "offsets.h"
++#ifdef __GLIBC__
+ #include <endian.h>
++#endif
+ 	.text
+ 
+ #define SREG(X) st.d $r##X, $r4, (LINUX_UC_MCONTEXT_GREGS + 8 * X)