perf tools: Rename build libperf to perf

Rename build libperf to perf, because it's used to build perf.

The libperf build object name will be used for libperf library.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190213123246.4015-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/arm64/Build

@@ -1,2 +1,2 @@
-libperf-y += util/
-libperf-$(CONFIG_DWARF_UNWIND) += tests/
+perf-y += util/
+perf-$(CONFIG_DWARF_UNWIND) += tests/

tools/perf/arch/arm64/tests/Build

@@ -1,4 +1,4 @@
-libperf-y += regs_load.o
-libperf-y += dwarf-unwind.o
+perf-y += regs_load.o
+perf-y += dwarf-unwind.o
 
-libperf-y += arch-tests.o
+perf-y += arch-tests.o

tools/perf/arch/arm64/util/Build

@@ -1,10 +1,10 @@
-libperf-y += header.o
-libperf-y += sym-handling.o
-libperf-$(CONFIG_DWARF)     += dwarf-regs.o
-libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
-libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
+perf-y += header.o
+perf-y += sym-handling.o
+perf-$(CONFIG_DWARF)     += dwarf-regs.o
+perf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
+perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
 
-libperf-$(CONFIG_AUXTRACE) += ../../arm/util/pmu.o \
+perf-$(CONFIG_AUXTRACE) += ../../arm/util/pmu.o \
 			      ../../arm/util/auxtrace.o \
 			      ../../arm/util/cs-etm.o \
 			      arm-spe.o