target/arm: Remove unnecessary '| 0xf0000000' from do_v7m_exception_exit()

In do_v7m_exception_exit(), there's no need to force the high 4
bits of 'type' to 1 when calling v7m_exception_taken(), because
we know that they're always 1 or we could not have got to this
"handle return to magic exception return address" code. Remove
the unnecessary ORs.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Acked-by: NAlistair Francis <alistair.francis@xilinx.com>
Message-id: 1505137930-13255-6-git-send-email-peter.maydell@linaro.org

target/arm/helper.c

@@ -6306,7 +6306,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
          */
         env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK;
         armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE);
-        v7m_exception_taken(cpu, type | 0xf0000000);
+        v7m_exception_taken(cpu, type);
         qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on existing "
                       "stackframe: failed exception return integrity check\n");
         return;
@@ -6348,7 +6348,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
         armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE);
         env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK;
         v7m_push_stack(cpu);
-        v7m_exception_taken(cpu, type | 0xf0000000);
+        v7m_exception_taken(cpu, type);
         qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on new stackframe: "
                       "failed exception return integrity check\n");
         return;