Fix x86_64 machine name for Linux and Darwin.

Author: marc0der

src/main/bash/sdkman-init.sh

@@ -44,7 +44,7 @@ function infer_platform() {
 	  i686)
 		echo "LinuxX32"
 		;;
-	  X86_64)
+	  x86_64)
 		echo "LinuxX64"
 		;;
 	  armv7l)
@@ -63,7 +63,7 @@ function infer_platform() {
 	  ;;
 	Darwin)
 	  case $machine in
-	  X86_64)
+	  x86_64)
 		echo "DarwinX64"
 		;;
 	  arm64)    

src/test/groovy/sdkman/specs/PlatformSpec.groovy

@@ -21,12 +21,12 @@ class PlatformSpec extends SdkmanEnvSpecification {
 		where:
 		kernel 		| machine	| platform
 		"Linux"		| "i686"	| "LinuxX32"
-		"Linux" 	| "X86_64"	| "LinuxX64"
+		"Linux" 	| "x86_64"	| "LinuxX64"
 		"Linux"		| "armv7l"	| "LinuxARM32"
 		"Linux"		| "armv8l"	| "LinuxARM64"
 		"Linux"		| "aarch64"	| "LinuxARM64"
 		"Linux"     | ""	    | "LinuxX64"
-		"Darwin"	| "X86_64"	| "DarwinX64"
+		"Darwin"	| "x86_64"	| "DarwinX64"
 		"Darwin"	| "arm64"	| "DarwinARM64"
 		"Darwin"    | ""        | "DarwinX64"
 		"MSYS64"	| "i686"	| "MSYS64"