Dwarf5ReadRangeList: remove duplicated declaration

Bug: Test Dwarf5ReadRangeList does not compile with GCC 10 because of
Change-Id: Ibeea82084bbf4c1d0e760a7bba14109401cf3639
duplicated declaration.
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2536913
Reviewed-by: Sterling Augustine <saugustine@google.com>
diff --git a/src/common/dwarf/dwarf2reader_die_unittest.cc b/src/common/dwarf/dwarf2reader_die_unittest.cc
index 57b8f71..4240fa8 100644
--- a/src/common/dwarf/dwarf2reader_die_unittest.cc
+++ b/src/common/dwarf/dwarf2reader_die_unittest.cc
@@ -574,10 +574,8 @@
   using dwarf2reader::DW_RLE_offset_pair;
   using dwarf2reader::DW_RLE_end_of_list;
   using dwarf2reader::DW_RLE_base_address;
-  using dwarf2reader::DW_RLE_offset_pair;
   using dwarf2reader::DW_RLE_start_end;
   using dwarf2reader::DW_RLE_start_length;
-  using dwarf2reader::DW_RLE_end_of_list;
   using dwarf2reader::DW_FORM_sec_offset;
   using dwarf2reader::DW_FORM_rnglistx;