espeak: Compile with uClibc++

Several Makefile cleanups.

Added PKG_BUILD_PARALLEL for faster compilation.

Several size optimizations applied.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

sound/espeak/patches/010-uclibcxx.patch

@@ -0,0 +1,21 @@
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -83,15 +83,15 @@ libespeak_SOURCES = speak_lib.cpp compiledict.cpp dictionary.cpp intonation.cpp
+ 
+ SRCS1=$(speak_SOURCES)
+ OBJS1=$(patsubst %.cpp,%.o,$(SRCS1))
+-LIBS1=-lstdc++ $(LIB_AUDIO) -lpthread $(EXTRA_LIBS)
++LIBS1=$(LIB_AUDIO) -lpthread $(EXTRA_LIBS)
+ 
+ SRCS2=$(libespeak_SOURCES)
+ OBJS2=$(patsubst %.cpp,x_%.o,$(SRCS2))
+-LIBS2=-lstdc++ $(LIB_AUDIO) -lpthread
++LIBS2=$(LIB_AUDIO) -lpthread
+ 
+ SRCS3 = espeak.cpp
+ OBJS3=$(patsubst %.cpp,%.o,$(SRCS3))
+-LIBS3=-lstdc++ -L . -lespeak
++LIBS3=-L . -lespeak
+ 
+ CXXFLAGS=-O2
+