Add Makefile options to build for the Raspberry Pi (armv7=0, arm_fpu=fvp2).

Makefile

Index: Makefile
diff --git a/Makefile b/Makefile
index 63cfbf4e49aad7e2329746222ddc5b0344bf61a7..db32a9532a15060e1b3ec1a0802ede09555b91da 100644
--- a/Makefile
+++ b/Makefile
@@ -91,13 +91,13 @@ endif
 ifeq ($(vfp2), off)
   GYPFLAGS += -Dv8_can_use_vfp2_instructions=false
 else
-  GYPFLAGS += -Dv8_can_use_vfp2_instructions=true
+  GYPFLAGS += -Dv8_can_use_vfp2_instructions=true -Darm_fpu=vfpv2
 endif
 # vfp3=off
 ifeq ($(vfp3), off)
   GYPFLAGS += -Dv8_can_use_vfp3_instructions=false
 else
-  GYPFLAGS += -Dv8_can_use_vfp3_instructions=true
+  GYPFLAGS += -Dv8_can_use_vfp3_instructions=true -Darm_fpu=vfpv3
 endif
 # debuggersupport=off
 ifeq ($(debuggersupport), off)
@@ -127,6 +127,10 @@ endif
 ifeq ($(hardfp), on)
   GYPFLAGS += -Dv8_use_arm_eabi_hardfloat=true
 endif
+# armv7=false
+ifeq ($(armv7), false)
+  GYPFLAGS += -Darmv7=0
+endif
 
 # ----------------- available targets: --------------------
 # - "dependencies": pulls in external dependencies (currently: GYP)