eeprom: idt_89hpesx: fix clang -Wformat warnings

eeprom: idt_89hpesx: fix clang -Wformat warnings

see warnings:
| drivers/misc/eeprom/idt_89hpesx.c:570:5: error: format specifies type
| 'unsigned char' but the argument has type 'u16' (aka 'unsigned short')
| [-Werror,-Wformat] memaddr);
-
| drivers/misc/eeprom/idt_89hpesx.c:579:5: error: format specifies type
| 'unsigned char' but the argument has type 'u16' (aka 'unsigned short')
| [-Werror,-Wformat] memaddr);
-
| drivers/misc/eeprom/idt_89hpesx.c:814:4: error: format specifies type
| 'unsigned short' but the argument has type 'unsigned int'
| [-Werror,-Wformat] CSR_REAL_ADDR(csraddr));

There's an ongoing movement to eventually enable the -Wformat flag for
clang. See: https://github.com/ClangBuiltLinux/linux/issues/378

The format specifier for idt_89hpesx.c:570 and 579 was `0x%02hhx`. The
part we care about `%hhx` describes a single byte format, wherein the
leftmost byte of our u16 type (of which memaddr is) is truncated.

example:
```
uint16_t x = 0xbabe;
printf("%hhx\n", x);
// output is: be
// we lost 'ba'
```

There exists a similar issue at idt_89hpesx.c:814 which involves the
CSR_REAL_ADDR macro. This macro returns a u16 but due to default
argument promotion for variadic functions (printf-like) actually
provides an int to the dev_err method.

My proposed solution is to expand the width of the format specifier to
fully encompass the provided argument (which is promoted to an int, see
below). I opted for '%x' as this specifies an unsigned hexadecimal
integer which, with a guarantee, can represent all the values of a u16.

As per C11 6.3.1.1:
(https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf)
`If an int can represent all values of the original type ..., the
value is converted to an int; otherwise, it is converted to an
unsigned int. These are called the integer promotions.`

Link: https://github.com/ClangBuiltLinux/linux/issues/378
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20220701232031.2639134-1-justinstitt@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>