aarch64: Add few missing system registers

aarch64: Add few missing system registers

This patch adds few missing system registers to GAS: LORC_EL1,
LOREA_EL1, LORN_EL1, LORSA_EL1, ICC_CTLR_EL3, ICC_SRE_ELX, ICH_VTR_EL2.

gas/ChangeLog:

2021-03-02  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>

	* testsuite/gas/aarch64/illegal-sysreg-7.d: New test.
	* testsuite/gas/aarch64/illegal-sysreg-7.l: New test.
	* testsuite/gas/aarch64/illegal-sysreg-7.s: New test.
	* testsuite/gas/aarch64/sysreg-7.d: New test.
	* testsuite/gas/aarch64/sysreg-7.s: New test.

opcodes/ChangeLog:

2021-03-02  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>

	* aarch64-opc.c: Add lorc_el1, lorea_el1, lorn_el1, lorsa_el1,
	icc_ctlr_el3, icc_sre_elx, ich_vtr_el2 system registers.