HID_HAPTIC=m prevents from linking

[Lucas GISSOT <lucas.gissot.pro@gmail.com>]

Hello,

I played with `make randconfig` and I managed to have a link error with
CONFIG_HID_HAPTIC=m
CONFIG_HID_MULTITOUCH=y

This is my first mail I send to this domain name, so I might do
something wrong, but it seems to me that the
#if IS_ENABLED(CONFIG_HID_HAPTIC)
in hid-haptic.h should be replaced by IS_BUILTIN(CONFIG_HID_HAPTIC) and
Kconfig updated.

This is the ld error:
  LD      .tmp_vmlinux1
ld: vmlinux.o: in function `mt_feature_mapping':
hid-multitouch.c:(.text+0xbfe86a): undefined reference to `hid_haptic_feature_mapping'
ld: vmlinux.o: in function `mt_input_configured':
hid-multitouch.c:(.text+0xbfeffa): undefined reference to `hid_haptic_input_configured'
ld: vmlinux.o: in function `mt_probe':
hid-multitouch.c:(.text+0xbff996): undefined reference to `hid_haptic_init'
ld: vmlinux.o: in function `mt_report':
hid-multitouch.c:(.text+0xc001a3): undefined reference to `hid_haptic_pressure_increase'
ld: hid-multitouch.c:(.text+0xc003bf): undefined reference to `hid_haptic_pressure_reset'
ld: vmlinux.o: in function `mt_input_mapping':
hid-multitouch.c:(.text+0xc00607): undefined reference to `hid_haptic_input_mapping'
ld: hid-multitouch.c:(.text+0xc00853): undefined reference to `hid_haptic_check_pressure_unit'
make[2]: *** [scripts/Makefile.vmlinux:72: vmlinux.unstripped] Error 1

I tested from a defaultconfig for x86_64 plus the changed on HID_HAPTIC
and HID_MULTITOUCH above

Please let me know if I made something wrong in the Cc or else.

Kind regards,

Lucas GISSOT
.