ACPI: PCC: Fix race condition by removing static qualifier

Local variable 'ret' in acpi_pcc_address_space_setup() is currently
declared as 'static'. This can lead to race conditions in a
multithreaded environment.

Remove the 'static' qualifier to ensure that 'ret' will be allocated
directly on the stack as a local variable.

Fixes: a10b1c9 ("ACPI: PCC: Setup PCC Opregion handler only if platform interrupt is available")
Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: lihuisong@huawei.com
Cc: 6.2+ <stable@vger.kernel.org> # 6.2+
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20251210132634.2050033-1-zhangpengjie2@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: Pengjie Zhang

drivers/acpi/acpi_pcc.c

@@ -52,7 +52,7 @@ acpi_pcc_address_space_setup(acpi_handle region_handle, u32 function,
 	struct pcc_data *data;
 	struct acpi_pcc_info *ctx = handler_context;
 	struct pcc_mbox_chan *pcc_chan;
-	static acpi_status ret;
+	acpi_status ret;
 
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (!data)