objdump: permit disassembling multiple individual functions

Compilers may split functions, e.g. into a "hot" and "cold" part, or
they may emit special case instantiations (e.g. as a result of IPA). It
can be helpful to be able to disassemble all of the parts or clones in
one go. Permit using "--disassemble=" multiple times.

binutils/testsuite/binutils-all/multi-3.d

@@ -0,0 +1,28 @@
+#name: objdump multiple --disassemble=
+#source: multi1.s
+#source: multi2.s
+#ld: -r
+#objdump: --disassemble=func --disassemble=func2 -wz
+# ECOFF disassembly omits local symbols, for whatever reason.
+#xfail: "alpha*-*-*ecoff" "alpha*-*-osf*"
+
+.*: +file format .*
+
+Disassembly of section .*:
+
+0+ <func>:
+[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#?[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#?[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+
+0+[0-1][0-9a-f] <func2>:
+[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#...
+0+[0-2][0-9a-f] <func2>:
+[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#?[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#?[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+
+0+[0-3][0-9a-f] <func>:
+[ 	]*[0-9a-f]+:	[0-9a-f][0-9a-f].*
+#pass

binutils/testsuite/binutils-all/objdump.exp

@@ -263,6 +263,7 @@ if { ![istarget "*-*-aix*"]
      && [file normalize "$LD"] == [file normalize "$objdir/../ld/ld-new"]} then {
     run_dump_test multi-1
     run_dump_test multi-2
+    run_dump_test multi-3
 }
 
 # Test objdump --disassemble=<symbol>