acpigen: Add ShiftLeft function helper

Provide a helper function for the ACPI shift left operator that
uses the same operator for the source and result.

ShiftLeft (OP, count, OP)

Signed-off-by: Duncan Laurie <dlaurie@google.com>
Change-Id: I66ee89bd1c4be583d0e892b02535bfa9514d488a
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46256
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/acpi/acpigen.c

@@ -1381,6 +1381,14 @@ void acpigen_write_else(void)
 	acpigen_write_len_f();
 }
 
+void acpigen_write_shiftleft_op_int(uint8_t src_result, uint64_t count)
+{
+	acpigen_emit_byte(SHIFT_LEFT_OP);
+	acpigen_emit_byte(src_result);
+	acpigen_write_integer(count);
+	acpigen_emit_byte(ZERO_OP);
+}
+
 void acpigen_write_to_buffer(uint8_t src, uint8_t dst)
 {
 	acpigen_emit_byte(TO_BUFFER_OP);