package/devel/gdb-arc: Add target GDB for ARC

ARC port of GDB is not yet upstream so we need to use
sources from Synopsys GitHub repo.

Given Synopys' commitment to upstream ARC support in GDB
in the nearest future it might be simpler to add a separate
package for ARC GDB instead of patching generic GDB package.
This way once ARC GDB stuff gets uptreamed we'll only need
to remove that new "gdb-arc" package.

Note 1 very minor change in generic gdb package was done -
it now depends on !arc (while "gdb-arc" depends on "arc").

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

package/devel/gdb-arc/patches/100-no_extern_inline.patch

@@ -0,0 +1,32 @@
+--- a/sim/common/sim-arange.c
++++ b/sim/common/sim-arange.c
+@@ -280,11 +280,7 @@ sim_addr_range_delete (ADDR_RANGE *ar, a
+   build_search_tree (ar);
+ }
+ 
+-#endif /* DEFINE_NON_INLINE_P */
+-
+-#if DEFINE_INLINE_P
+-
+-SIM_ARANGE_INLINE int
++int
+ sim_addr_range_hit_p (ADDR_RANGE *ar, address_word addr)
+ {
+   ADDR_RANGE_TREE *t = ar->range_tree;
+@@ -301,4 +297,4 @@ sim_addr_range_hit_p (ADDR_RANGE *ar, ad
+   return 0;
+ }
+ 
+-#endif /* DEFINE_INLINE_P */
++#endif /* DEFINE_NON_INLINE_P */
+--- a/sim/common/sim-arange.h
++++ b/sim/common/sim-arange.h
+@@ -73,7 +73,7 @@ extern void sim_addr_range_delete (ADDR_
+ 
+ /* Return non-zero if ADDR is in range AR, traversing the entire tree.
+    If no range is specified, that is defined to mean "everything".  */
+-SIM_ARANGE_INLINE int
++extern int
+ sim_addr_range_hit_p (ADDR_RANGE * /*ar*/, address_word /*addr*/);
+ #define ADDR_RANGE_HIT_P(ar, addr) \
+   ((ar)->range_tree == NULL || sim_addr_range_hit_p ((ar), (addr)))