acpi: Export functions to write sized values

At present only acpigen_write_integer() is exported for use by other code.
But in some cases it is useful to call the specific function depending on
the size of the value.

Export these functions and add a test.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
[bmeng: Fix the "new blank line at EOF" warning]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

include/acpi/acpigen.h

@@ -172,6 +172,52 @@ void acpigen_pop_len(struct acpi_ctx *ctx);
  */
 char *acpigen_write_package(struct acpi_ctx *ctx, int nr_el);
 
+/**
+ * acpigen_write_byte() - Write a byte
+ *
+ * @ctx: ACPI context pointer
+ * @data: Value to write
+ */
+void acpigen_write_byte(struct acpi_ctx *ctx, unsigned int data);
+
+/**
+ * acpigen_write_word() - Write a word
+ *
+ * @ctx: ACPI context pointer
+ * @data: Value to write
+ */
+void acpigen_write_word(struct acpi_ctx *ctx, unsigned int data);
+
+/**
+ * acpigen_write_dword() - Write a dword
+ *
+ * @ctx: ACPI context pointer
+ * @data: Value to write
+ */
+void acpigen_write_dword(struct acpi_ctx *ctx, unsigned int data);
+
+/**
+ * acpigen_write_qword() - Write a qword
+ *
+ * @ctx: ACPI context pointer
+ * @data: Value to write
+ */
+void acpigen_write_qword(struct acpi_ctx *ctx, u64 data);
+
+/**
+ * acpigen_write_zero() - Write zero
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_zero(struct acpi_ctx *ctx);
+
+/**
+ * acpigen_write_one() - Write one
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_one(struct acpi_ctx *ctx);
+
 /**
  * acpigen_write_integer() - Write an integer
  *