Fix sim build when configured with --enable-plugins

Fix sim build when configured with --enable-plugins

	* common/Make-common.in: Use lt_cv_dlopen_libs under PLUGINS
	condition.
	* common/acinclude.m4: Define lt_cv_dlopen_libs.
	* arm/configure: Regenerate.
	* avr/configure: Regenerate.
	* bfin/configure: Regenerate.
	* common/configure: Regenerate.
	* cr16/configure: Regenerate.
	* cris/configure: Regenerate.
	* d10v/configure: Regenerate.
	* erc32/configure: Regenerate.
	* frv/configure: Regenerate.
	* h8300/configure: Regenerate.
	* igen/configure: Regenerate.
	* iq2000/configure: Regenerate.
	* lm32/configure: Regenerate.
	* m32c/configure: Regenerate.
	* m32r/configure: Regenerate.
	* m68hc11/configure: Regenerate.
	* mcore/configure: Regenerate.
	* microblaze/configure: Regenerate.
	* mips/configure: Regenerate.
	* mn10300/configure: Regenerate.
	* moxie/configure: Regenerate.
	* ppc/configure: Regenerate.
	* rl78/configure: Regenerate.
	* rx/configure: Regenerate.
	* sh/configure: Regenerate.
	* sh64/configure: Regenerate.
	* testsuite/configure: Regenerate.
	* v850/configure: Regenerate.