kernel: remove platform_has() infrastructure

The only use case of the platform_has() infrastructure has been
removed again, so remove the whole feature.

Signed-off-by: Juergen Gross <[e-mail]>
Tested-by: Oleksandr Tyshchenko <[e-mail]> # Arm64 guest using Xen
Reviewed-by: Stefano Stabellini <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Juergen Gross <[e-mail]>

MAINTAINERS

···
 F:	Documentation/devicetree/bindings/iio/chemical/plantower,pms7003.yaml
 F:	drivers/iio/chemical/pms7003.c
 
-PLATFORM FEATURE INFRASTRUCTURE
-M:	Juergen Gross <[e-mail]>
-S:	Maintained
-F:	arch/*/include/asm/platform-feature.h
-F:	include/asm-generic/platform-feature.h
-F:	include/linux/platform-feature.h
-F:	kernel/platform-feature.c
-
 PLDMFW LIBRARY
 M:	Jacob Keller <[e-mail]>
 S:	Maintained

include/asm-generic/Kbuild

···
 mandatory-y += pci.h
 mandatory-y += percpu.h
 mandatory-y += pgalloc.h
-mandatory-y += platform-feature.h
 mandatory-y += preempt.h
 mandatory-y += rwonce.h
 mandatory-y += sections.h

include/asm-generic/platform-feature.h

···
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_GENERIC_PLATFORM_FEATURE_H
-#define _ASM_GENERIC_PLATFORM_FEATURE_H
-
-/* Number of arch specific feature flags. */
-#define PLATFORM_ARCH_FEAT_N	0
-
-#endif /* _ASM_GENERIC_PLATFORM_FEATURE_H */

include/linux/platform-feature.h

···
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _PLATFORM_FEATURE_H
-#define _PLATFORM_FEATURE_H
-
-#include <linux/bitops.h>
-#include <asm/platform-feature.h>
-
-/* The platform features are starting with the architecture specific ones. */
-#define PLATFORM_FEAT_N				(0 + PLATFORM_ARCH_FEAT_N)
-
-void platform_set(unsigned int feature);
-void platform_clear(unsigned int feature);
-bool platform_has(unsigned int feature);
-
-#endif /* _PLATFORM_FEATURE_H */

kernel/Makefile

···
 	    cpu.o exit.o softirq.o resource.o \
 	    sysctl.o capability.o ptrace.o user.o \
 	    signal.o sys.o umh.o workqueue.o pid.o task_work.o \
-	    extable.o params.o platform-feature.o \
+	    extable.o params.o \
 	    kthread.o sys_ni.o nsproxy.o \
 	    notifier.o ksysfs.o cred.o reboot.o \
 	    async.o range.o smpboot.o ucount.o regset.o

kernel/platform-feature.c

···
-// SPDX-License-Identifier: GPL-2.0
-
-#include <linux/bitops.h>
-#include <linux/cache.h>
-#include <linux/export.h>
-#include <linux/platform-feature.h>
-
-#define PLATFORM_FEAT_ARRAY_SZ  BITS_TO_LONGS(PLATFORM_FEAT_N)
-static unsigned long __read_mostly platform_features[PLATFORM_FEAT_ARRAY_SZ];
-
-void platform_set(unsigned int feature)
-{
-	set_bit(feature, platform_features);
-}
-EXPORT_SYMBOL_GPL(platform_set);
-
-void platform_clear(unsigned int feature)
-{
-	clear_bit(feature, platform_features);
-}
-EXPORT_SYMBOL_GPL(platform_clear);
-
-bool platform_has(unsigned int feature)
-{
-	return test_bit(feature, platform_features);
-}
-EXPORT_SYMBOL_GPL(platform_has);