riscv: add linux/bpf_perf_event.h to UAPI compile-test coverage

I can compile this for ARCH=riscv with CONFIG_UAPI_HEADER_TEST=y.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>

usr/include/Makefile

@@ -74,10 +74,6 @@ no-header-test += asm/stat.h
 no-header-test += linux/bpf_perf_event.h
 endif
 
-ifeq ($(SRCARCH),riscv)
-no-header-test += linux/bpf_perf_event.h
-endif
-
 ifeq ($(SRCARCH),sparc)
 no-header-test += asm/stat.h
 no-header-test += asm/uctx.h