ACPICA: Improve exception handling for GPE block installation.

1) Return an actual status value from acpi_ev_get_gpe_xrupt_block.
2) Don't clobber the status when exiting acpi_ev_install_gpe_block.

References: https://bugs.acpica.org/show_bug.cgi?id=1019
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/acpica/evgpeblk.c

@@ -87,9 +87,9 @@ acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
 		return_ACPI_STATUS(status);
 	}
 
-	gpe_xrupt_block = acpi_ev_get_gpe_xrupt_block(interrupt_number);
-	if (!gpe_xrupt_block) {
-		status = AE_NO_MEMORY;
+	status =
+	    acpi_ev_get_gpe_xrupt_block(interrupt_number, &gpe_xrupt_block);
+	if (ACPI_FAILURE(status)) {
 		goto unlock_and_exit;
 	}
 
@@ -112,7 +112,7 @@ acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 
 unlock_and_exit:
-	status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
+	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 	return_ACPI_STATUS(status);
 }