ACPI: EC: Enable EC support on LoongArch by default

Commit a6021aa2 ("ACPI: EC: make EC support compile-time
conditional") only enable ACPI_EC on X86 by default, but the embedded
controller is also widely used on LoongArch laptops so we also enable
ACPI_EC for LoongArch.

The laptop driver cannot work without EC, so also update the dependency
of LOONGSON_LAPTOP to let it depend on APCI_EC.

Fixes: a6021aa2 ("ACPI: EC: make EC support compile-time conditional")
Reported-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Tested-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://patch.msgid.link/20241217073704.3339587-1-chenhuacai@loongson.cn


[ rjw: Added Fixes: ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>