Re: PR26580, Size and alignment of commons vs as-needed shared lib

Some MIPS targets, for reasons I didn't analyse, use the larger common
symbol in a shared lib rather than a smaller common in an executable.
That doesn't seem unreasonable, so allow that to pass for pr26580-2.

bfin-elf complains about not supporting copy relocs, but it's quite
silly to want a copy reloc for common symbols, so leave the fail
there.  mn10300-elf and score-elf both fail the test with "PHDR
segment not covered by LOAD segment".  Other tests fail similarly so
one more doesn't hurt.  The failure is a consequence of supporting
dynamic objects but setting EMBEDDED in ld scripts.

	PR 26580
	* testsuite/ld-elf/pr26580-2.sd: Accept undefined symbol.

ld/ChangeLog

@@ -1,3 +1,7 @@
+2020-09-10  Alan Modra  <amodra@gmail.com>
+
+	* testsuite/ld-elf/pr26580-2.sd: Accept undefined symbol.
+
 2020-09-10  Alan Modra  <amodra@gmail.com>
 
 	* testsuite/ld-plugin/lto-18b.c (select): Remove.

ld/testsuite/ld-elf/pr26580-2.sd

@@ -1,4 +1,4 @@
 
 #...
-.* 8 OBJECT  GLOBAL DEFAULT .* one
+.* (8 OBJECT  GLOBAL DEFAULT .*|0 OBJECT  GLOBAL DEFAULT  UND) one
 #pass