Don't implicitly dereference DW_CFA_def_cfa_expression.

The specification isn't entirely clear. Follow the gdb interpretation.

Bug: 73954823
Test: libunwindstack_test
Change-Id: If72717f54eed84e442f43af19e615143a9796b68
diff --git a/libunwindstack/tests/DwarfCfaTest.cpp b/libunwindstack/tests/DwarfCfaTest.cpp
index 68dc30c..7395b04 100644
--- a/libunwindstack/tests/DwarfCfaTest.cpp
+++ b/libunwindstack/tests/DwarfCfaTest.cpp
@@ -737,6 +737,8 @@
   ASSERT_TRUE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x200, 0x284, &loc_regs));
   ASSERT_EQ(0x284U, this->dmem_->cur_offset());
   ASSERT_EQ(1U, loc_regs.size());
+  ASSERT_EQ(DWARF_LOCATION_VAL_EXPRESSION, loc_regs[CFA_REG].type);
+  ASSERT_EQ(0x81U, loc_regs[CFA_REG].values[0]);
 
   ASSERT_EQ("", GetFakeLogPrint());
   ASSERT_EQ("", GetFakeLogBuf());