xbox1/360: remove cygpath requirement to allow older mingw toolchains to work

Makefile.libretro

@@ -11,6 +11,8 @@ BACKSLASH :=
 BACKSLASH := \$(BACKSLASH)
 filter_out1 = $(filter-out $(firstword $1),$1)
 filter_out2 = $(call filter_out1,$(call filter_out1,$1))
+unixpath = $(subst \,/,$1)
+unixcygpath = $(subst C:,/c,$(subst c:,/c,$(call unixpath,$1)))
 
 ifeq ($(platform),)
 	platform = unix
@@ -423,13 +425,13 @@ LDFLAGS += -DLL
 # Windows MSVC 2003 Xbox 1
 else ifeq ($(platform), xbox1_msvc2003)
 TARGET := $(TARGET_NAME)_libretro_xdk1.lib
-CC  = "CL.exe"
-CXX  = "CL.exe"
-LD   = "lib.exe"
+CC  = CL.exe
+CXX  = CL.exe
+LD   = lib.exe
 
-export INCLUDE := $(XDK)/xbox/include
-export LIB := $(XDK)/xbox/lib
-PATH := $(shell IFS=$$'\n'; cygpath -w "$(XDK)/xbox/bin/vc71"):$(PATH)
+export INCLUDE := $(XDK)\xbox\include
+export LIB := $(XDK)\xbox\lib
+PATH := $(call unixcygpath,$(XDK)/xbox/bin/vc71):$(PATH)
 
 PSS_STYLE :=2
 CFLAGS   += -D_XBOX -D_XBOX1
@@ -439,13 +441,13 @@ STATIC_LINKING=1
 # Windows MSVC 2010 Xbox 360
 else ifeq ($(platform), xbox360_msvc2010)
 TARGET := $(TARGET_NAME)_libretro_xdk360.lib
-CC  = "cl.exe"
-CXX  = "cl.exe"
-LD   = "lib.exe"
+CC  = cl.exe
+CXX  = cl.exe
+LD   = lib.exe
 
 export INCLUDE := $(XEDK)/include/xbox
 export LIB := $(XEDK)/lib/xbox
-PATH := $(shell IFS=$$'\n'; cygpath -w "$(XEDK)/bin/win32"):$(PATH)
+PATH := $(call unixcygpath,$(XEDK)/bin/win32):$(PATH)
 
 PSS_STYLE :=2
 CFLAGS   += -D_XBOX -D_XBOX360