Subzero: switch from llvm-objdump to objdump for lit tests (for LLVM merge)

tests_lit/llvm2ice_tests/mangle.ll

 ; Tests the Subzero "name mangling" when using the "llvm2ice --prefix"
 ; option.  Also does a quick smoke test of -ffunction-sections.
 
 ; REQUIRES: allow_dump
 ; RUN: %p2i -i %s --args --verbose none -ffunction-sections | FileCheck %s
 ; TODO(stichnot): The following line causes this test to fail.
-; RUIN: %p2i -i %s --args --verbose none \
-; RUIN:     | llvm-mc -triple=i686-none-nacl -filetype=obj
+; RUIN: %p2i --assemble --disassemble -i %s --args --verbose none \
+; RUIN:   | FileCheck %s
 ; RUN: %p2i -i %s --args --verbose none --prefix Subzero -ffunction-sections \
-; RUN:      | FileCheck --check-prefix=MANGLE %s
+; RUN:   | FileCheck --check-prefix=MANGLE %s
 
 define internal void @FuncC(i32 %i) {
 entry:
   ret void
 }
 ; FuncC is a C symbol that isn't recognized as a C++ mangled symbol.
 ; CHECK-LABEL: .text.FuncC
 ; CHECK: FuncC:
 ; MANGLE-LABEL: .text.SubzeroFuncC
 ; MANGLE: SubzeroFuncC:
@@ skipping 115 matching lines @@
   ret void
 }
 
 ; Test that unmangled (non-C++) strings don't have substitutions updated.
 define internal void @foo_S_S0_SZ_S() {
 ; MANGLE-LABEL: .text.Subzerofoo_S_S0_SZ_S
 ; MANGLE: Subzerofoo_S_S0_SZ_S:
 entry:
   ret void
 }